Explanation
Latency, also known as round-trip time (RTT), is the time it takes for a data packet to travel from a source to its destination and back again. It is a key indicator of network performance and can be used to identify fluctuations that may impact the user experience of an application.
Bandwidth, loss, and cyclic redundancy check (CRC) are other important network performance metrics, but they are not directly related to the application team's requirement to monitor for fluctuations in RTT.
References:
CompTIA Network+ N10-008 Exam Objectives, Objective 1.6: Network Performance Monitoring CompTIA Network+ N10-008 Study Guide, Chapter 10: Network Performance Monitoring and Troubleshooting Additional Notes:
The network team can use a variety of tools and techniques to monitor RTT, such as ping, traceroute, and network monitoring software.
When setting up alerts, the network team should consider the acceptable range of RTT for the application. They should also configure alerts to trigger at different levels of severity, so that they can take prompt action to resolve any issues.

Explanation
Coaxial cable is a type of cable that consists of a central copper conductor surrounded by an insulating layer and a braided metal shield. Coaxial cable is commonly used to connect a cable modem to an ISP by transmitting data over cable television networks. Coaxial cable can support high bandwidth and long distances with minimal interference or attenuation. References:
https://partners.comptia.org/docs/default-source/resources/comptia-network-n10-008-exam-objectives-(2-0),
https://www.techopedia.com/definition/4027/coaxial-cable

Explanation
A helper address is an IP address that is configured on a router interface to forward DHCP broadcast messages to a DHCP server on another LAN. A DHCP broadcast message is a message that a workstation sends when it needs to obtain an IP address from a DHCP server. Since broadcast messages are not routed across different networks, a helper address is needed to relay the DHCP broadcast message to the DHCP server on another network. References: https://www.comptia.org/training/books/network-n10-008-study-guide (page 199)

Explanation
A client-to-site VPN and a split-tunnel VPN are the best options for designing a secure remote access scheme that meets the given requirements. A client-to-site VPN allows users at multiple locations to access corporate resources over the internet by creating a secure tunnel between their devices and a VPN concentrator on the corporate network1. A split-tunnel VPN allows the on-premises equipment to handle only the traffic that is destined for the corporate resources, while the non-corporate traffic is routed directly to the internet without passing through the VPN tunnel2. This reduces the bandwidth and processing load on the corporate network and improves the performance of the remote access.
References:
Remote Access - N10-008 CompTIA Network+ : 4.41
comptia Network+ : Remote Access Methods And Network Monitoring2