Which of the following well-known service ports/services should be disabled if they are not being used?

A.
Telnet.

B.
FTP.

C.
Both of the above.

D.
None of the above

Explanation:
Telnet and FTP ports that are open to the Internet serve as one of the bigger security risks to the company. All ports that are not being used should be disabled.
References:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, pp. 457-458.