Intermittent VoIP call quality issues that occur during peak hours are a classic symptom of network congestion caused by voice and data traffic competing for the same network resources. According to CompTIA Core 1 (220-1201) networking and VoIP objectives, one of the most effective solutions is to configure VLANs to separate voice and data traffic.
By placing VoIP devices on a dedicated voice VLAN, the network can apply Quality of Service (QoS) policies that prioritize voice packets over standard data traffic. This reduces latency, jitter, and packet loss, which are the primary causes of poor call quality. VLAN separation ensures that even during heavy data usage, voice traffic remains clear and reliable.
Routing calls through a gigabit port does not address traffic prioritization and is unlikely to resolve congestion during peak usage. Installing shielded network cables only helps in environments with excessive electromagnetic interference, which would affect performance consistently-not intermittently. Increasing the VoIP bit rate would actually worsen congestion by consuming more bandwidth.
CompTIA emphasizes VLAN implementation and QoS as best practices for VoIP deployments, especially when call quality degrades under high network utilization.
References:CompTIA A+ Core 1 (220-1201) Official Study Guide - VoIP, VLANs, and Network Performance

Overheating is a common cause of projectors shutting down after extended use. A clogged air filter can cause overheating, resulting in intermittent shutdowns.
From CompTIA A+ 220-1101 Official Study Guide, Objective 4.1 - Troubleshooting displays:
"If a projector shuts down after running for a period, clean or replace the filter to prevent overheating and automatic shutdown." Verified Source:
CompTIA A+ Core 1 (220-1101) Official Study Guide, Chapter 4: Display Troubleshooting CompTIA Exam Objectives 220-1101, Domain 4.1

Most meeting or conferencing applications default to the built-in laptop camera unless manually changed.
When an external camera is connected, the software may continue to use the default device, resulting in a blank preview, especially if the internal camera is disabled, covered, or malfunctioning. CompTIA A+ stresses verifying correct device selection when peripherals are installed.
Selecting the correct camera source is a quick, non-invasive test that resolves the issue in the majority of cases. The technician should open the application's video settings and choose the external webcam from the camera dropdown menu.
Replacing the camera (B) is premature without confirming configuration. Updating software (C) is beneficial but will not resolve a simple input-selection error. Checking the cable (D) is a valid step if the preview still fails after selecting the device.
Thus, the correct next step is to select the proper camera source.

Inlaser printers, thefuser unitis responsible formelting the toner onto the paperusing heat and pressure. If the toner rubs off easily, it's a clear sign thefuser is failing or not heating properly. Replacing the fuser will ensure the toner bonds correctly to the paper.
Option B (Drum):Transfers the image, but doesn't fuse the toner.
Option C (Developer roller):Applies toner to the drum wouldn't cause toner to rub off.
Option D (Discharge lamp):Prepares the drum for a new image; not related to toner adhesion.
CompTIA A+ Core 1 Exam Objective Reference:
Objective 3.7: Given a scenario, troubleshoot common printer problems.

The most likely cause of a laptop screen dimming consistently in the evening is an ambient light/adaptive brightness feature. Many laptops include an ambient light sensor that automatically changes screen brightness based on room lighting conditions. As natural light decreases later in the day, the sensor detects a darker environment and reduces brightness to save power and reduce eye strain. Because this behavior occurs at a predictable time (evening) and the user can temporarily correct it by manually increasing brightness, it strongly points to automatic brightness control rather than a hardware failure.
Changing the Ambient light setting (disabling adaptive brightness/auto-brightness) provides a permanent fix by preventing the system from adjusting brightness in response to lighting changes. While battery/power plans can also dim displays to conserve energy, that usually correlates with running on battery power or specific power-saving modes-not a consistent evening pattern. Graphics settings typically affect resolution, scaling, or driver features and are not the primary control for time-of-day dimming behavior. Scheduled tasks could theoretically run display-related scripts, but that is uncommon compared to built-in ambient light adaptation. Therefore, adjusting the ambient light/adaptive brightness setting is the best CompTIA A+ answer.