While securing a network it is decided to allow active FTP connections into the network. Which of the
following ports MUST be configured to allow active FTP connections? (Select TWO).

A.
20

B.
21

C.
22

D.
68

E.
69

Explanation:
FTP (File Transfer Protocol) makes use of ports 20 and 21
Incorrect Answers:
C: TCP port 22 is used for all protocols encrypted by SSH, including SFTP, SHTTP, SCP, SExec, and slogin.
D: Port 68 TCP/UDP is used by Bootstrap Protocol (BOOTP) Client; as well Dynamic Host Configuration
Protocol (DHCP).
E: Port 69 is used for Trivial File Transfer Protocol (TFTP).

Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis, 2014, p. 51
http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers