What happens while disabling ESMTP inspection?

What happens while disabling ESMTP inspection?

A.
All SMTP commands are prevented from traversing the security appliance.

B.
Only the data, helo, mail, noop, quit, rcpt, and rset SMTP commands are allowed through the
security appliance.

C.
All SMTP commands are allowed through the security appliance, and potential mail server
vulnerabilities are exposed.

D.
Only the auth, ehlo, etrn, help, saml, send, soml, and vrfy extended SMTP commands are
allowed through the security appliance.