You are trying to initiate an SSH connection to a remote router and are getting rejected with an error code of 0. Which of these might be the cause of the error?

A.
The routers are using different SSH versions.

B.
You are trying to log in using invalid credentials.

C.
The RSA key pair is not properly configured on the SSH client.

D.
The RSA key pair is not properly configured on the SSH server.