You have a w2k8 IIS server. Your company uses SMTP email. Now you want to prevent the sending
of unauthorized email and restrict SMTP only to internal servers without affecting the current mail
flow. What should you do?

A.
Block all outbound email with a windows firewall rule

B.
Disable the high alerts in windows defender

C.
Enable tls-encryption on the outbound security

D.
You add a SMTP relay restriction that allows SMTP-relaying only from the servers in your domain