Explanation/Reference:
Explanation:
Requirements for EIGRP authentication
The time must be properly configured on all routers. Refer to Configuring NTP for more information.

A working EIGRP configuration is recommended.

If we have option "Key-Chain", instead of "Passwords" then option C would also be correct.
References: https://www.cisco.com/c/en/us/support/docs/ip/enhanced-interior-gateway-routing-protocol- eigrp/82110-eigrp-authentication.html