What is the result of disabling ESMTP inspection?

What is the result of disabling ESMTP inspection?

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

B.
Only the auth, ehlo, etrn, help, saml, send, soml, and vrfy extended 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.
All SMTP commands are prevented from traversing the security appliancE.