What is the maximum length for a certificate ID in AWS IAM?

What is the maximum length for a certificate ID in AWS IAM?

A.
1024 characters

B.
512 characters

C.
64 characters

D.
128 characters

Explanation:
The maximum length for a certificate ID is 128 characters.
http://docs.aws.amazon.com/IAM/latest/UserGuide/LimitationsOnEntities.html