An administrator needs to be able to have a router securely communicate with a network management system. The connections must be authenticated but not encrypted. While meeting these requirements…

The `snmp-server group v3 auth` command creates an SNMPv3 group with `authNoPriv` security, meaning messages are authenticated using a hash algorithm but not encrypted, precisely meeting the requirement for authentication without encryption. This configuration provides integrity and authentication without confidentiality for SNMP traffic.

The `priv` keyword in `snmp-server group v3 priv write` would enable encryption (privacy) in addition to authentication, which contradicts the requirement that connections must "not be encrypted."

SNMPv2c does not provide robust user-based authentication; it relies on community strings for basic access control and does not offer the granular authentication mechanisms required for "securely communicate" in the context of authentication without encryption.

Similar to C, SNMPv2c does not offer the strong, user-based authentication or the `authNoPriv` security model specified in the question's requirements for secure communication without encryption.