In network management, QoS is used to do which of the following?

• A. Control bandwidth.
• B. Change DHCP scope.
• C. Update routing tables.
• D. Manage server OS patches.

Answer: (A)

Quality of Service focuses on managing how bandwidth is allocated and how traffic is prioritized to meet performance requirements for different applications. By shaping, policing, queuing, and marking packets, QoS ensures latency-sensitive traffic such as voice or video gets the necessary resources even when the network is congested. That’s why the best answer is that QoS controls bandwidth, because allocating and limiting bandwidth directly affects how smoothly different traffic types perform.

DHCP scope relates to IP address management, not traffic quality. Updating routing tables is about determining paths for packets, not prioritizing or reserving bandwidth. Managing server OS patches is about maintenance and security updates, not network traffic behavior.