An administrator has implemented a new SMTP service on a server. A public IP address translates to the internal SMTP server. The administrator notices many sessions to the server, and gets notification that the servers public IP address is now reported in a spam real-time block list. Which of the following is wrong with the server?

A.
SMTP open relaying is enabled.

B.
It does not have a spam filter.

C.
The amount of sessions needs to be limited.

D.
The public IP address is incorrect.