CompTIA Security+ Question K-50

An organization recently switched from a cloud-based email solution to an in-house email server. The firewall needs to be modified to allow for sending and receiving email. Which of the following ports should be open on the firewall to allow for email traffic? (Select THREE).

A. TCP 22
B. TCP 23
C. TCP 25
D. TCP 53
E. TCP 110
F. TCP 143
G. TCP 445

Answer: C,E,F

Explanation:
Port 25 is used by Simple Mail Transfer Protocol (SMTP) for routing e-mail between mail servers. Port 110 is used for Post Office Protocol v3 (POP3), which is an application-layer Internet standard protocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection. Port 143 is used by Internet Message Access Protocol (IMAP) for the management of email messages.