Which of the following protocols and ports are used for SNMP (Simple Network Management Protocol)?

SNMP, or Simple Network Management Protocol, is primarily utilized for network management and monitoring. It operates using a client-server model, where the SNMP manager (client) communicates with SNMP agents (servers) to gather information about the network devices.

The protocol uses the User Datagram Protocol (UDP) for its communication, which is favored in network management due to its low overhead and speed, as it does not require a connection to be established prior to sending data. SNMP typically listens for requests on port 161, which is designated for the general SNMP requests. Port 162 is used for receiving SNMP traps, which are unsolicited messages sent from agents to the manager, but the main communication for managing and querying devices is conducted over port 161.

Therefore, the correct option accurately identifies that SNMP utilizes UDP on port 161 for its operations, making it the appropriate choice.