Answer:
The five rules are described as follows:
Rule A permits the inbound Simple Mail Transfer Protocol (SMTP) connection.
Rule B permits the inbound Simple Mail Transfer Protocol (SMTP) connection.
Rule C permits the outbound Simple Mail Transfer Protocol (SMTP) connection.
Rule D permits the outbound Simple Mail Transfer Protocol (SMTP) connection.
Rule E does not perform any action. Thus it is when the action is denied.
Explanation:
Rule A allows information transfer of the incoming email from the external server to the internal remote server, thus this allows an inbound connection.
Rule B allows information transfer of the incoming email from the remote server to the external remote server, thus this allows an inbound connection.
Rule C allows information transfer of outgoing email from the external server to the internal remote server, thus this allows an outbound connection.
Rule D allows information transfer of the outgoing email from the remote server to the external remote server, thus this allows an outbound connection.
Rule E does not allow any action in either direction thus it is when action is denied.