Final answer:
Telnet, SSH, SNMP, and SYSLOG are all part of the management plane, which relates to the administration and monitoring of networking equipment.
Step-by-step explanation:
In the field of computer networking, the functions described are part of the management plane, which deals with the administration and monitoring of network equipment. Telnet and SSH (Secure Shell) are both protocols used for secure remote management of devices, allowing network administrators to access and control devices over a network.
SNMP (Simple Network Management Protocol) is used for monitoring network-attached devices for conditions that warrant administrative attention. SYSLOG is a standard for message logging, allowing the collection and storage of log messages from different types of equipment in a central repository. These protocols are essential in managing a computer network's infrastructure.
The plane that deals with Telnet, SSH, SNMP, and SYSLOG is the Management plane. The Management plane is responsible for managing and controlling network devices and services.
Therefore answer is iii. Management plane.