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CompTIA A+ study materials
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CompTIA A+ practice questions

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Question 1Mobile Devices

A technician is replacing the storage drive in a modern, thin laptop. Which drive form factor is designed for this type of system?

  1. mSATA
  2. M.2 Correct answer.
  3. 3.5-inch SATA
  4. 2.5-inch SATA

Explanation

Thin laptops use M.2 modules, which are small rectangular cards that mount flat against the system board and can carry either a SATA or an NVMe interface. Larger spinning-disk and older SSD form factors require a drive bay that slim chassis do not have.

Question 2Mobile Devices

Which wireless technology lets a smartphone complete a payment when the phone is held a few centimeters from a payment terminal?

  1. Infrared
  2. NFC Correct answer.
  3. Bluetooth
  4. Wi-Fi Direct

Explanation

Near Field Communication operates at a range of only a few centimeters, which is what makes tap-to-pay terminals practical and secure. The very short range ensures the phone must be intentionally presented to the reader.

Question 3Mobile Devices

A user wants to expand the storage of an Android smartphone with removable media. Which card type fits the phone's slot?

  1. xD-Picture
  2. microSD Correct answer.
  3. Full-size SD
  4. CompactFlash

Explanation

Smartphones use the microSD form factor, which is the smallest common flash memory card and is designed for space-constrained devices. Larger card formats physically will not fit a phone slot.

Question 4Mobile Devices

Which feature lets a smartphone share its cellular data connection with a laptop over Wi-Fi?

  1. Roaming
  2. Synchronization
  3. Airplane mode
  4. Mobile hotspot Correct answer.

Explanation

A mobile hotspot turns the phone into a small Wi-Fi access point that forwards traffic over the cellular data network; the equivalent over a cable or Bluetooth link is called tethering. The laptop connects to the phone just as it would to any Wi-Fi network.

Question 5Mobile Devices

Which component identifies a subscriber to the cellular carrier and can be moved to another compatible phone?

  1. IMEI
  2. SIM card Correct answer.
  3. Wi-Fi MAC address
  4. Build number

Explanation

The SIM (or its embedded eSIM profile) holds the subscriber identity and authentication keys, so moving it to another unlocked phone carries the account with it. The IMEI and MAC address are hardware identifiers tied to a specific device.

Question 6Mobile Devices

A company-owned phone has been lost. Which action removes company data from the device the next time it connects to the network?

  1. Factory reset
  2. Enrollment
  3. Remote wipe Correct answer.
  4. Airplane mode

Explanation

A remote wipe is issued by the MDM server or a device-finding service and executes when the device next checks in, erasing or removing protected data without physical access. A factory reset requires the technician to hold the device.

Question 7Mobile Devices

A laptop whose display can rotate 360 degrees and fold back for use as a tablet is best described by which term?

  1. Convertible Correct answer.
  2. Docking station
  3. Ultrabook
  4. Digitizer

Explanation

A convertible (2-in-1) laptop uses a hinged display that rotates a full 360 degrees, letting the chassis fold flat into tablet form. The term describes the physical design rather than the internal components.

Question 8Mobile Devices

Which connector is reversible, can carry power and video, and is now the standard charging port on most Android phones?

  1. Micro-USB
  2. USB-C Correct answer.
  3. Mini-USB
  4. Lightning

Explanation

USB-C is a reversible 24-pin connector that supports power delivery, video output such as DisplayPort alternate mode, and high-speed data. Micro-USB and Mini-USB are directional legacy connectors with no video capability.

Question 9Mobile Devices

A laptop display shows a very faint image that is only visible when a flashlight is aimed at the screen, while an external monitor works normally. Which component has most likely failed?

  1. The touch digitizer
  2. The display cable
  3. The video adapter
  4. The LCD panel backlight Correct answer.

Explanation

An LCD does not produce its own light, so if the backlight fails the image is still being drawn but cannot be seen without an external light source. A working external monitor confirms the graphics adapter is producing a valid signal.

Question 10Mobile Devices

A user wants corporate email, calendar, and contacts on a phone, along with enforced PIN requirements and the ability to wipe data remotely. Which mail service type should be configured?

  1. Exchange (ActiveSync) Correct answer.
  2. SMTP
  3. POP3
  4. IMAP

Explanation

Exchange ActiveSync synchronizes mail, calendar, and contacts and carries security policy enforcement such as PIN requirements and remote wipe to the device. Plain mail protocols synchronize messages only and cannot apply device policies.

Question 11Mobile Devices

A user wants a single cable from a laptop to a dock that supplies power, video, and USB data. Which port type supports all three?

  1. Thunderbolt 3 over USB-C Correct answer.
  2. USB 2.0 Type-A
  3. VGA
  4. eSATA

Explanation

Thunderbolt 3 uses the USB-C connector and multiplexes power delivery, DisplayPort video, and PCIe/USB data on one cable, which is what makes single-cable docking possible. Older ports carry only one of those signal types.

Question 12Mobile Devices

Which MDM capability blocks email access from devices that are missing security patches or a screen lock?

  1. Geofencing
  2. Compliance policy Correct answer.
  3. Content locker
  4. Profile removal

Explanation

A compliance policy defines minimum device conditions, such as OS version, patch level, and screen lock, and conditional access enforces them by denying corporate resources when a device is noncompliant. Rules are evaluated against reported device state each time access is requested.

Question 13Mobile Devices

A company buys smartphones for employees and allows them to install personal apps and use the devices for personal calls. Which deployment model is this?

  1. CYOD
  2. BYOD
  3. VDI
  4. COPE Correct answer.

Explanation

Corporate-owned, personally enabled (COPE) means the organization owns and manages the hardware but permits personal use alongside business use. BYOD and CYOD both involve the employee choosing or owning the device.

Question 14Mobile Devices

An employee uses a personal phone for work email. IT must be able to remove company email and documents without deleting personal photos. Which MDM feature provides this?

  1. Full device wipe
  2. Containerization with selective wipe Correct answer.
  3. Geofencing
  4. Remote lock

Explanation

Containerization separates corporate data into a managed partition, so a selective (enterprise) wipe removes only that partition and leaves personal content intact. A full device wipe would erase everything on the phone.

Question 15Mobile Devices

Which mail protocol keeps messages on the server and synchronizes read and unread state across a phone, tablet, and PC?

  1. SMTP
  2. IMAP Correct answer.
  3. SNMP
  4. POP3

Explanation

IMAP stores messages on the server and lets multiple clients view the same mailbox, so folder contents and read status stay consistent between devices. POP3 is designed to download mail to a single client instead.

Question 16Mobile Devices

A frequent international traveler wants to add a local carrier plan to a phone that has no empty SIM tray. Which technology allows the plan to be downloaded to the device?

  1. NFC
  2. MicroSD
  3. eSIM Correct answer.
  4. Bluetooth pairing

Explanation

An eSIM is a soldered chip that stores one or more carrier profiles downloaded over the air, so a new local plan can be added without a physical card. The embedded chip replaces the removable tray slot.

Question 17Mobile Devices

A user has misplaced a phone but believes it is somewhere in the office. Which feature should be used first to make the phone ring?

  1. Airplane mode
  2. Find My / Find Device Correct answer.
  3. Mobile hotspot
  4. Remote wipe

Explanation

Device-finding services can ring, locate, lock, or erase a registered device, and ringing is the least destructive option for a phone that is merely misplaced. Erasing should be reserved for devices that are unrecoverable.

Question 18Mobile Devices

A technician connected a projector to a Windows laptop and the image is duplicated instead of extended. Which shortcut opens the display mode selector?

  1. Win+P Correct answer.
  2. Ctrl+P
  3. Alt+Tab
  4. Ctrl+Shift+Esc

Explanation

Windows+P opens the projection pane, where the technician can choose PC screen only, Duplicate, Extend, or Second screen only. The choice is applied immediately and then remembered for that display configuration.

Question 19Mobile Devices

A tablet will be used as a self-service check-in terminal in a lobby. Which control ensures that only the check-in app can run?

  1. Auto-rotate
  2. Kiosk mode Correct answer.
  3. Airplane mode
  4. Guest Wi-Fi

Explanation

Kiosk (single-app or lockdown) mode restricts the device to one application and typically blocks the home screen, settings, and task switching. This prevents lobby visitors from reaching any other function of the tablet.

Question 20Mobile Devices

Which setting secures mail traffic between a phone and the mail server when the account uses port 993?

  1. Static IP
  2. SSL/TLS Correct answer.
  3. SMTP relay
  4. None (cleartext)

Explanation

Port 993 is the IMAP over SSL/TLS port, so the client must have encryption enabled for the connection to succeed. Encryption protects both the credentials and the message contents in transit.

Question 21Mobile Devices

A phone fails to join the corporate Wi-Fi network, which uses EAP-TLS, even though the username and password are correct. Other devices connect successfully. What is the most likely missing item?

  1. An enabled SSID broadcast
  2. A client certificate installed on the phone Correct answer.
  3. The pre-shared key
  4. A MAC filtering exemption

Explanation

EAP-TLS authenticates both sides with digital certificates, so the supplicant needs a valid client certificate issued by the organization's CA in addition to the network profile. Password-based EAP methods do not apply to this configuration.

Question 22Mobile Devices

A company must configure 200 new tablets with Wi-Fi, apps, and restrictions before handing them to users, without staging each one by hand. Which approach accomplishes this?

  1. Manual setup using one shared Apple ID on every tablet
  2. Emailing a configuration profile to each user
  3. Cloning settings from a master tablet with a USB hub
  4. Apple Business Manager with automated device enrollment to an MDM Correct answer.

Explanation

Automated device enrollment ties newly purchased serial numbers to the organization's MDM, so the devices configure themselves from a predefined blueprint at first boot with no hands-on staging. This is the zero-touch provisioning model.

Question 23Mobile Devices

Which second factor is most resistant to interception by an attacker who controls the cellular network?

  1. A time-based code from an authenticator app Correct answer.
  2. A knowledge-based security question
  3. An SMS one-time code
  4. An email one-time code

Explanation

Authenticator apps generate codes locally from a shared secret, so nothing travels over a network that the attacker could capture or redirect. Codes delivered by SMS or email depend on channels that can be intercepted or taken over.

Question 24Mobile Devices

After a mail account was configured on a phone, messages the user deletes on the phone also disappear from the webmail inbox, and folders are not synchronized. Which protocol is in use?

  1. SMTP
  2. Exchange ActiveSync
  3. POP3 Correct answer.
  4. IMAP

Explanation

POP3 clients download messages and by default delete them from the server when they are removed locally, and the protocol has no concept of synchronizing folder structure or read state. IMAP and ActiveSync both keep the mailbox authoritative on the server.

Question 25Mobile Devices

Which item on a mobile device holds the carrier's preferred roaming list, which is refreshed by a carrier provisioning update?

  1. APN
  2. IMEI
  3. PRL Correct answer.
  4. ICCID

Explanation

The preferred roaming list tells the radio which networks and channels to use first, and carriers push updated lists over the air. The IMEI identifies hardware, the ICCID identifies the SIM, and the APN defines the data connection parameters.

Question 26Mobile Devices

Which charging habit best preserves the long-term capacity of a modern smartphone battery?

  1. Keeping the charge mostly between 20% and 80% Correct answer.
  2. Leaving the phone plugged in at 100% whenever possible
  3. Storing the phone at 100% charge in a hot car
  4. Fully draining the battery to 0% every day

Explanation

Lithium-ion cells age fastest when held at very high or very low states of charge. Keeping the charge in a moderate range reduces that stress and extends usable capacity.

Question 27Mobile Devices

A user is trying to pair new wireless earbuds with a phone, but the earbuds do not appear in the Bluetooth device list. What should the user do first?

  1. Enable airplane mode on the phone
  2. Put the earbuds into pairing mode Correct answer.
  3. Turn on NFC on the phone
  4. Connect the earbuds to the phone with a USB cable

Explanation

Bluetooth devices must be in discoverable or pairing mode before a phone can see them. This is separate from turning on the phone's Bluetooth radio.

Question 28Mobile Devices

Which wireless technology allows a phone to complete a tap-to-pay transaction at a payment terminal?

  1. Bluetooth pairing
  2. NFC Correct answer.
  3. Infrared beaming
  4. GPS

Explanation

NFC is designed for very short-range exchanges and is the technology used by contactless payment terminals. The phone must be held close to the terminal, but no pairing is required.

Question 29Mobile Devices

A user wants the phone to require the screen lock after two minutes of inactivity. Which setting should be configured?

  1. Screen lock timeout Correct answer.
  2. Do Not Disturb schedule
  3. Display sleep timeout
  4. Auto-rotate

Explanation

The screen lock timeout sets how long the device stays unlocked after the display turns off. It is distinct from the display timeout, which only controls when the screen goes dark.

Question 30Mobile Devices

A traveling user needs to share a phone's cellular data connection with a laptop. Which feature should be enabled?

  1. VPN
  2. Mobile hotspot Correct answer.
  3. Bluetooth file transfer
  4. NFC

Explanation

Mobile hotspot, also called tethering, shares the phone's cellular data connection with another device over Wi-Fi, USB, or Bluetooth. It is the feature intended for this purpose.

Question 31Mobile Devices

An Android user must install a business app from the vendor's website because it is not offered in the Play Store. Which setting should be enabled for that source?

  1. Root the phone
  2. Allow unknown sources Correct answer.
  3. USB debugging
  4. Enable developer options

Explanation

Android blocks installs from outside the verified store until the user permits that source. The permission is granted for a source or app, not by enabling developer tools.

Question 32Mobile Devices

Why should a user install an operating system update when the phone prompts for one?

  1. It unlocks the bootloader permanently
  2. It increases the phone's storage capacity
  3. It provides security patches and bug fixes Correct answer.
  4. It removes the carrier's SIM lock

Explanation

OTA updates commonly include security patches, defect fixes, and sometimes new features. Installing them reduces exposure to known vulnerabilities.

Question 33Mobile Devices

A navigation app reports that it cannot determine the phone's position even outdoors. Which phone setting should be checked first?

  1. NFC
  2. Location services Correct answer.
  3. Mobile hotspot
  4. Bluetooth tethering

Explanation

Location services must be on for the phone to use GPS, Wi-Fi, and cell signals to determine position. A navigation app cannot calculate a fix if the location toggle is off.

Question 34Mobile Devices

A remote worker needs to reach internal file shares from a phone while on a cellular network. Which connection provides an encrypted tunnel to the corporate network?

  1. VPN Correct answer.
  2. Mobile hotspot
  3. NFC
  4. Bluetooth tethering

Explanation

A VPN encrypts traffic between the phone and the corporate network, allowing access to internal resources over an untrusted link. Hotspot and tethering share a connection rather than tunnel it.

Question 35Mobile Devices

A photo-editing app requests access to the user's contacts, but the app has no feature that needs them. What is the best action?

  1. Grant access so the app runs faster
  2. Deny the permission Correct answer.
  3. Disable the phone's screen lock
  4. Root the phone to audit the app

Explanation

The principle of least privilege says an app should receive only the permissions its features require. Denying an unnecessary contact permission reduces the app's access to private data.

Question 36Mobile Devices

A user wants contacts, calendar events, and email to appear automatically on a new phone. Which approach is most appropriate?

  1. Move the old SD card to the new phone
  2. Copy contacts over Bluetooth
  3. Enable account sync Correct answer.
  4. Factory reset the new phone

Explanation

Account-based synchronization keeps contacts, calendars, and mail in a cloud service and restores them when the same account is added to a new device. It avoids manual copying.

Question 37Mobile Devices

A phone's display shows the image correctly, but taps and swipes are not recognized. Which component is most likely faulty?

  1. Wireless charging coil
  2. Battery
  3. Digitizer Correct answer.
  4. Speaker

Explanation

The digitizer is the touch-sensing layer that converts taps and swipes into input; a working image with no touch response points to it. The other listed components do not handle touch input.

Question 38Mobile Devices

What security risk is introduced by rooting an Android phone?

  1. The battery will charge more slowly
  2. App sandbox protections can be bypassed Correct answer.
  3. The phone can no longer connect to Wi-Fi networks
  4. The screen will no longer rotate automatically

Explanation

Rooting grants superuser control, which can break the Android sandbox that isolates apps from each other and from system data. Malicious or poorly written apps can then access data they normally could not.

Question 39Mobile Devices

A company enrolls employee-owned Android phones and wants to prevent corporate data in managed apps from being copied into personal apps. Which mechanism is designed for this?

  1. A mobile hotspot
  2. A VPN profile
  3. A longer screen lock timeout
  4. A work profile Correct answer.

Explanation

An Android work profile creates a separate managed environment for corporate apps and data. MDM policies can then block copying or sharing from that profile into personal apps.

Question 40Mobile Devices

A phone shows strong cellular signal bars, but web pages fail to load over mobile data. Which setting is the most likely cause?

  1. The phone has airplane mode turned on
  2. The screen brightness is too low
  3. Bluetooth is turned off
  4. An incorrect APN Correct answer.

Explanation

The APN tells the phone which carrier gateway and settings to use for mobile data. If it is wrong, the phone can register on the network and show signal while data sessions fail.

Question 41Networking

Which TCP port does HTTPS use by default?

  1. TCP 3389
  2. TCP 80
  3. TCP 443 Correct answer.
  4. TCP 21

Explanation

HTTPS wraps HTTP inside a TLS session and listens on TCP 443 by default. Browsers fall back to TCP 80 only when a site is configured for plain HTTP.

Question 42Networking

A technician needs to manage a Linux server's command line securely across an untrusted network. Which protocol should be used?

  1. SSH Correct answer.
  2. SNMP
  3. Telnet
  4. RDP

Explanation

SSH provides an encrypted channel for remote shell access, typically over TCP 22. Because all traffic, including credentials, is encrypted, it is safe to use across untrusted links.

Question 43Networking

A Windows workstation reports the address 169.254.13.7. What does this indicate?

  1. The host is using an IPv6 tunnel
  2. The default gateway is set incorrectly
  3. The DHCP server was unreachable Correct answer.
  4. The host has been given a static public address

Explanation

When a DHCP client receives no lease, Windows self-assigns an address from the 169.254.0.0/16 link-local range by using APIPA. Such a host cannot route beyond its own link until it obtains a valid lease.

Question 44Networking

Which address does a host use to verify that its own TCP/IP stack is working?

  1. 255.255.255.255
  2. 169.254.0.1
  3. 127.0.0.1 Correct answer.
  4. 0.0.0.0

Explanation

The entire 127.0.0.0/8 range is reserved for loopback, and 127.0.0.1 is the conventional address for that purpose. Traffic sent there never reaches a network adapter.

Question 45Networking

Which connector is used to terminate twisted-pair Ethernet cable?

  1. BNC
  2. RJ11
  3. LC
  4. RJ45 Correct answer.

Explanation

The RJ45 (8P8C) plug is the standard termination for Cat 5e, Cat 6, and similar twisted-pair Ethernet cable. It carries four wire pairs into a switch, patch panel, or wall jack.

Question 46Networking

A host must send a packet to an address outside its own subnet. Where does the host send the frame?

  1. Its DNS server
  2. Its gateway Correct answer.
  3. Its DHCP server
  4. Its loopback address

Explanation

A host compares the destination address with its own subnet mask. When the destination is remote, the frame is addressed to the MAC of the configured default gateway, which forwards it onward.

Question 47Networking

Which Windows command displays the path that packets take to a remote host?

  1. ping
  2. tracert Correct answer.
  3. netstat
  4. ipconfig

Explanation

Tracert sends probes with increasing time-to-live values and reports each router that returns an ICMP timeout. This builds a hop-by-hop list of the route to the target.

Question 48Networking

In a star topology, all network devices connect to which central component?

  1. A firewall
  2. A modem
  3. A patch panel
  4. A switch Correct answer.

Explanation

A star topology places an active central device, usually a switch, between every endpoint. Each host has its own dedicated link, so a single cable failure affects only that host.

Question 49Networking

A DHCP server listens for client requests on which port?

  1. UDP 68
  2. UDP 67 Correct answer.
  3. TCP port 67
  4. UDP 69

Explanation

DHCP servers receive client messages on UDP 67 and reply to the client's UDP 68. DHCP is a UDP protocol because it must work before a host has any IP configuration.

Question 50Networking

Which DNS record type identifies the mail servers that accept email for a domain?

  1. MX Correct answer.
  2. A
  3. TXT
  4. CNAME

Explanation

An MX record names the mail exchanger for a domain and includes a preference value so senders can try servers in order. Without a valid MX record, inbound mail cannot be delivered.