Refer to the exhibit. An engineer attempts to establish BGP peering between router CORP and two ISP routers. What is the root cause for the failure between CORP and ISP#2?

While an SHA-1 configuration on ISP#2 could cause a mismatch if CORP is using a different method like MD5, a general 'password mismatch' is a more direct and common cause of authentication failure.

BGP peering relies on matching authentication credentials between neighbors, and a password mismatch between router CORP and ISP#2 will prevent the BGP session from successfully establishing due to failed authentication.

An extended access control list on router CORP, unless it specifically blocks BGP traffic (TCP port 179) between the peers, is not typically the root cause of a BGP authentication failure.

Incorrect MD5 authorization on router ISP#2 would lead to a password mismatch, so 'password mismatch' is a more precise description of the resulting issue rather than just incorrect configuration.