CompTIA Updated 220-1201 Exam Questions and Answers by advik

DNS contains different record types that serve specific purposes. To determine where incoming email should be delivered for a particular domain, DNS uses an MX (Mail Exchange) record. CompTIA A+ identifies MX records as essential for routing mail from external senders to the appropriate mail server assigned to a domain.

The MX record specifies:

The mail server hostname responsible for receiving messages

Priority values, which determine which server to try first

The server destination for SMTP traffic

When someone sends an email, the sending mail server queries DNS to find the MX record for the recipient’s domain. The SMTP server then relays the email to the server listed in that record.

CNAME is used for aliasing hostnames, TXT is used for verification/security (SPF, DKIM), and AAAA maps a hostname to an IPv6 address. None of these direct email delivery. Only MX records are designed to instruct mail servers where to deliver incoming email.

Thus, the correct answer is MX.

Bluetooth audio issues are typically related to distance and signal strength, not internet connectivity or Wi-Fi access points. Bluetooth devices—especially headsets—generally have a limited effective range of around 10 meters (33 feet) for Class 2 Bluetooth, which is common in consumer laptops and headsets. When the user leaves the room and walks into adjacent offices, they are likely moving beyond the optimal Bluetooth range or passing through walls that weaken the signal.

CompTIA A+ highlights that Bluetooth uses low-power radio frequencies easily disrupted by physical obstructions, distance, and interference. Since the laptop remains stationary and the user moves, the headset becomes progressively further from the laptop, causing intermittent audio dropouts, stuttering, or loss of connection.

The number of APs (A) is irrelevant because the headset is not using Wi-Fi. Mesh mode (C) applies only to wireless AP-to-AP communication. The internet connection (D) is high-quality fiber and conference calls work fine when stationary, so the issue is not bandwidth or WAN throughput.

Thus, the most likely cause is that the user is moving in and out of Bluetooth range.

VoIP traffic is highly sensitive to latency, jitter, and packet loss, even when overall internet bandwidth appears sufficient. According to CompTIA Core 1 (220-1201) networking and VoIP troubleshooting objectives, normal speed test results do not guarantee good VoIP performance because speed tests measure throughput, not real-time traffic prioritization.

In this scenario, users experience choppy audio and lag, which are classic symptoms of voice packets competing with regular data traffic during periods of network utilization. Enabling Quality of Service (QoS) on the router allows the network to prioritize VoIP traffic over less time-sensitive data such as web browsing, file downloads, or streaming. This ensures voice packets are transmitted with minimal delay, improving call clarity and reliability.

Configuring PoE only supplies power to VoIP phones and does not affect call quality. Changing wireless encryption standards does not resolve latency or prioritization issues. MAC address filtering is a security feature and has no impact on VoIP performance.

CompTIA emphasizes QoS as a key solution for resolving VoIP performance issues in environments where bandwidth exists but voice traffic is not properly prioritized.