CompTIA A+ Practice Test (220-1201)

The 2.4 GHz band propagates through walls better than the higher-frequency 5 GHz band. In addition, narrowing the channel width from 80 MHz to the standard 20 MHz reduces noise, increases the signal-to-noise ratio, and generally improves range at the cost of peak throughput-an acceptable trade-off for low-bandwidth devices such as a barcode scanner. Enabling 20 MHz operation on the 2.4 GHz radio therefore gives the scanner a stronger, farther-reaching signal. Enabling DFS channels still keeps the client on 5 GHz, which suffers more attenuation. Disabling 2.4 GHz forces all devices onto 5 GHz, worsening the problem. Changing from WPA2 to WPA3 affects security, not RF coverage.

A burning smell indicates that an electrical component-most often the power supply, voltage-regulator circuitry on the motherboard, or a shorted cable-is overheating. Continuing to operate the system risks fire and further damage. The correct first response is to power the computer down and disconnect it from the AC outlet so current can no longer flow. Only after the unit is safely de-energized should you open the case or run diagnostics. Running memory tests, updating firmware, or re-applying thermal paste leave the hazard energized and could worsen damage or cause personal injury.

802.11ac, also known as Wi-Fi 5, operates exclusively in the 5GHz frequency band. It supports higher data rates compared to previous standards, specifically due to wider channel bandwidths (80 MHz and 160 MHz), more spatial streams, and more efficient data encoding. While it offers improved performance and less interference compared to the 2.4GHz band, it does not include the 60GHz frequency; that band is used by the 802.11ad standard. 802.11ac also supports Multi-User Multiple Input Multiple Output (MU-MIMO) technology, which is an enhancement over the MIMO in previous standards.

The correct answer is to replace the battery. A bulging battery indicates that it has undergone physical changes likely due to overcharging, age, or defect, and can pose a safety risk including potential fire hazard. Continuing to use a battery in this condition can cause further damage to the device and is a safety risk. Simply letting the device cool down or resetting the device software won't address the root cause of the overheating and battery bulging.

Ports 137 and 139 are associated with NetBIOS/NetBT services. Port 137 is used by NetBIOS for name resolution services, allowing machines on a local network to find each other by name, whereas port 139 is used for session services, facilitating communication between computers. Even though port 135 is also used for RPC Endpoint Mapper, it's not directly related to NetBIOS/NetBT services, and 445 is reserved for Microsoft-DS (Directory Services) over SMB, which facilitates file sharing without the NetBIOS layer.

A frequent cause of "paper not feeding" or "load paper" errors is a mismatch between the printer's configured paper size or media type and what is actually loaded. Most modern printers stop the job until the settings match. Verifying and, if necessary, correcting the paper size and type settings is therefore the next logical step before moving on to firmware updates or hardware replacement.

When a storage device is confirmed to be powered and internally connected but not visible in the file explorer, the next step should be to check the disk management utility. It is possible the drive does not have an assigned drive letter, or it is not initialized, which would prevent it from appearing in the file explorer, but it might still be visible within the disk management. The other provided answers are less likely to resolve the issue at this stage. Updating interface controller drivers or replacing the interface data cable would be premature because if these were the issues, the drive typically wouldn't appear in disk management either. Reviewing external connections would not be relevant since the issue is with an internally mounted storage device.

A Virtual Private Network (VPN) provides an encrypted tunnel to connect to networks. It can be used to securely connect from a home office to a corporate network or as an additional layer of security when using public wireless networks (e.g. the free WiFi at a coffee shop).

Running legacy software on newer operating systems might lead to compatibility issues; therefore, utilizing virtual machines allows an older operating system to be used, ensuring that the legacy software remains operational. This is dissimilar from sandboxing, which is used to run potentially untrusted programs without risking the host system, and resource efficiency, which addresses the optimization of physical resources but not compatibility with older software. Users refers to the people operating the software, not the software compatibility itself.

Metered utilization is the correct answer because it allows the company to pay only for the resources it consumes. This characteristic aligns with the company's goal to match costs with actual usage and also provides the flexibility to adjust to changing demands. Rapid elasticity, while related, mainly addresses the speed and agility with which resources can be scaled, rather than the cost alignment aspect. High availability is an important factor for maintaining uptime and accessibility, but does not directly impact the cost aspect as metered usage does. File synchronization is a feature that ensures consistency of files across systems, but it does not affect the billing or the cost structure based on actual usage.

An unmanaged switch is a low-cost, plug-and-play device that immediately begins forwarding traffic without any configuration. Because it lacks features such as VLAN support, SNMP monitoring, or port security, it is less expensive than a managed switch and perfectly suited to simply adding additional Ethernet ports. A managed switch would provide capabilities the business does not need and therefore costs more. A router's main purpose is to connect different networks, not merely to add ports, and consumer routers typically offer only a few LAN ports. A hub is outdated technology that broadcasts every frame out all ports, which reduces performance and raises security concerns.

The probe needs to push a small, one-way message without establishing or maintaining a session. UDP is a connectionless protocol, so it does not perform the three-way handshake, sequencing, acknowledgments, or flow-control operations that TCP uses. This absence of session management keeps the header small (8 bytes vs. TCP's 20+ bytes) and processing overhead low, making UDP ideal when speed and reduced bandwidth matter more than guaranteed delivery. TCP, on the other hand, is connection-oriented; its handshake, acknowledgments, and retransmission features add latency and additional bytes-unnecessary for a simple, best-effort status message. The option claiming UDP provides built-in flow control is incorrect, as this is a feature of TCP. The option claiming TCP can broadcast packets is also incorrect; TCP is a unicast protocol and does not support broadcasting.

The primary function of a switch in a wired network is to connect devices together on the same network by using MAC addresses to forward data frames to the appropriate destination. Unlike a router, a switch does not facilitate the connection between multiple networks or manage IP address assignments. It is not used for terminating a DSL or cable line, which is the typical function of a modem.

Verifying that the monitor is turned on and connected properly is a foundational step in troubleshooting display issues. This addresses the simplest cause where the monitor itself might be powered off or disconnected, which would result in a blank screen. If the monitor receives proper power and connection but the screen remains blank, the technician can then proceed to assess more complex hardware components. Checking for POST beeps or proprietary crash screens would not be the initial steps as they would not be present if the monitor is simply turned off. Similarly, inspecting motherboard components would come later in the troubleshooting process once basic external checks are completed.

Capacitive trackpads detect very small changes in an electrostatic field. A thin film of moisture, sweat, or dirt can register as additional touches, so the pointer appears to jump or drift. Cleaning and drying the pad usually restores normal tracking.

Out-of-date or corrupted drivers can also cause touchpad-only problems, but those issues usually appear after an operating-system or driver update and are less common than surface contamination. Re-calibrating sensitivity or disabling multi-touch features affects how intentional input is interpreted, not the phantom touches produced by contaminants.

Step 1 in the CompTIA troubleshooting methodology is to identify the problem. Gather information from the user, observe the device, review error messages or logs, and note any recent changes. Only after clearly defining the problem do you proceed to forming a theory, testing, planning a fix, and so forth. While corporate policies must always be considered before making changes, that consideration precedes implementation later in the process, not the initial fact-finding stage.

When multiple users experience the same issue of inverted page orientation despite having the correct settings in their applications, this suggests that the problem is at the printer level rather than with individual software configurations. Checking and modifying the default printing preferences in the printer's network settings or on the printer server is a logical next step, as these settings override individual user settings. This action preserves user application settings and alters the orientation for all printed documents from that printer. Directly adjusting the printer's hardware control panel settings could also resolve the issue, but network settings are generally responsible for multiple user issues. Modifying the original document's properties does not address the multiple user symptom, and reinstalling on one client machine would not fix the issue for all users.

Running the update in a VM allows developers to discover many functional or compatibility problems in an isolated environment and roll back quickly by reverting to a snapshot. This greatly reduces the likelihood that the update will disrupt the live environment, but it does not guarantee zero downtime because some issues-such as differences in hardware drivers, real-world load, or integration with external services-may still surface only after production deployment.

Sharing a device's cellularly connected internet to nearby devices is called tethering.

Mobile Device Management (MDM) platforms provide centralized control over smartphones and tablets. Through an MDM console, administrators can deploy configuration profiles (including corporate email, Wi-Fi, VPN, and security policies) and send commands such as Remote Wipe to erase a device that is lost or stolen. POP3, personal cloud-storage apps, and wireless security protocols do not provide these management or wipe functions.