Free A+ practice test
12 original questions written by our editors against the official CompTIA exam domains. They are not real exam questions. Pick an answer to see the explanation.
-
Mobile devices
A user wants to connect her laptop to two monitors, a wired keyboard, a mouse and wired Ethernet at her desk, and charge it, using one cable. The laptop has a Thunderbolt-capable USB-C port. What should the technician recommend?
Show answer
Answer: C. A USB-C or Thunderbolt dock carries display, data, network and power over one cable. Bluetooth peripherals do not add displays or Ethernet. A USB 2.0 hub lacks the bandwidth for video and does not charge the laptop, and VGA is an analog video port, not a single-cable dock.
-
Networking
A user cannot reach the internet or any network share. ipconfig shows the address 169.254.37.12 with a 255.255.0.0 mask. What is the most likely cause?
Show answer
Answer: A. A 169.254.x.x address is an APIPA address, which Windows assigns itself when no DHCP server answers. A wrong DNS server or gateway would still leave a valid DHCP address. A static address would not normally be in the APIPA range.
-
Hardware
A small office server has four identical drives. The owner wants the array to survive one drive failure while keeping as much usable capacity as possible. Which RAID level fits best?
Show answer
Answer: B. RAID 5 survives one drive failure and loses only one drive's worth of capacity to parity, giving three drives of usable space. RAID 0 has no fault tolerance. RAID 1 mirrors pairs and RAID 10 stripes mirrors, both using half the total capacity.
-
Virtualization and cloud computing
A company wants to stop buying physical servers. It will rent virtual machines, storage and networking from a provider, but its own team will install and patch the operating systems and applications. Which cloud service model is this?
Show answer
Answer: A. In IaaS the provider supplies the infrastructure and the customer manages the OS and everything above it. PaaS also manages the OS and runtime for you, SaaS delivers finished applications, and DaaS delivers hosted desktops.
-
Hardware and network troubleshooting
Pages from a laser printer look fine when they come out, but the toner smears and rubs off when touched. Which component is most likely failing?
Show answer
Answer: B. The fuser uses heat and pressure to bond toner to the paper; if it fails, toner sits loose on the page. A worn pickup roller causes misfeeds, a transfer belt problem causes missing or misplaced toner, and a damaged drum causes repeating marks or lines.
-
Hardware and network troubleshooting
Users in an office break room report that their 2.4 GHz Wi-Fi drops every day around lunchtime, while other areas are fine. What is the most likely cause and fix?
Show answer
Answer: A. Microwave ovens operate near 2.4 GHz and cause interference when in use, which matches a problem tied to place and time of day. DHCP exhaustion would affect new connections everywhere, a hidden SSID does not cause timed drops, and firmware would not explain a location-specific pattern.
-
Operating systems
A Windows 11 PC shows random errors after an unexpected power loss, and the technician suspects corrupted protected system files. Which command should be run from an elevated prompt to check and repair them?
Show answer
Answer: A. System File Checker (sfc /scannow) scans protected Windows system files and replaces corrupted ones. chkdsk checks the file system and disk, not system file versions. gpupdate refreshes Group Policy and ipconfig /flushdns clears the DNS cache.
-
Operating systems
On a Linux workstation, a script file cannot be run because it lacks execute permission. Which command gives the owner permission to execute it?
Show answer
Answer: B. chmod changes file permissions, and u+x adds execute permission for the owner. chown changes ownership, not permissions. sudo runs a command with elevated rights but does not add the execute bit, and grep searches text.
-
Security
A technician is setting up a new SOHO wireless router for a small business. All laptops and phones are less than two years old. Which wireless security setting should be used?
Show answer
Answer: B. WPA3 is the current and strongest Wi-Fi security standard, and modern devices support it. WEP and WPA-TKIP are outdated and easy to break. An open network with a captive portal does not encrypt wireless traffic.
-
Security
A company notices visitors are following employees through a badge-controlled door without scanning a badge. Which physical control best prevents this?
Show answer
Answer: A. An access control vestibule lets only one person through at a time, which stops tailgating. Cameras record the problem but do not prevent it. Screen lock settings are a logical control, and a sign-in sheet does not stop someone from following an employee in.
-
Software troubleshooting
A user reports that her browser home page has changed to an unknown search site and her searches are redirected to ad-filled pages. Other browsers on the same PC work normally. What should the technician check first?
Show answer
Answer: B. A changed home page and redirected searches limited to one browser point to a browser hijacker, often installed as an extension. Faulty RAM causes crashes rather than redirects, a network fault would affect every browser, and activation status does not change browser settings.
-
Operational procedures
A technician needs to know how to safely handle and dispose of a leaking toner cartridge. Which document should be consulted?
Show answer
Answer: C. A safety data sheet describes hazards, handling, first aid and disposal for a chemical product such as toner. A warranty card covers repairs, an acceptable use policy covers how staff use IT systems, and change management forms track planned changes.