A customer wants to implement X.509 certificate authentication on their users. They want to extract
the username from each certificate for accounting and single sign-on purposes. The correct
username syntax lies within the common name portion of the certificate’s subject field. Which
username template should you use on the certificate authentication server’s configuration?

A.
<certDN.CN>

B.
<certDN.SN>

C.
<certAttr.altName.CN>

D.
<certAttr.altName.SN>