Explanation
When installing RAM into a server that will be used as a VM host, it is recommended to install ECC (Error-Correcting Code) RAM to help prevent errors that can cause virtual machines to crash. References:
https://www.servermonkey.com/blog/ecc-vs-non-ecc-ram-what-are-the-differences.html When installing RAM into a rackmount server that will be used as a VM host, it would be best to install ECC (Error Correcting Code) RAM which can detect and correct common types of data corruption.

Explanation
The most likely reason for a computer showing an APIPA address after being plugged into a network port is that the PC is unable to contact a DHCP server1. Automatic Private IP Addressing (APIPA) is a DHCP fail-safe that protects a computer system from failure. It invokes a standby mechanism for local Internet Protocol version 4 (IPv4) networks supported by Microsoft Windows. With APIPA, DHCP clients can obtain IP addresses even when DHCP servers are not functional1. The other options are less likely to be the cause of the issue1.

Explanation
The two sets of colors on the motherboard indicate that it supports dual-channel memory, which doubles the bandwidth available to the memory controller. Dual-channel memory requires two identical memory modules to be installed in pairs in the correct slots to work effectively. In this case, the user can install two identical RAM modules to enable dual-channel memory, which will provide better performance when using multimedia applications that consume a lot of memory.

Explanation
The component that should be upgraded first is the RAM. When multiple applications are being utilized, the system's response time slows down drastically. This is because the computer is running out of memory. Upgrading the RAM will allow the computer to store more data in memory, which will improve performance when multiple applications are being used

Explanation
The issue of video but no audio on a projector in a conference room can be resolved by utilizing an HDMI connection between the PC and the projector. HDMI supports both video and audio signals and is commonly used to connect a PC to a projector for presentations. Changing the input on the projector to VGA, changing the output on the PC to DVI, or modifying the projector's refresh rate will not resolve the issue. References:
CompTIA A+ Certification Exam: Core 1 - Objective 2.5