What can be done to almost securely secure the server room from unauthorized access?

A.
Locks on the server chassis

B.
Locks on the server rack

C.
Entrance passwords to enter the server room

D.
Installed server security software

Explanation:
The first introduction to server network security for most employees occurs at the entrance to the server room.
Incorrect
Answers:
A, B, C: Yes, all this is security measures, but it does not keep them from entering the server room. The question states about unauthorized access to the server room.
References:
Charles J. Brooks, Server+ Certification Exam Cram 2 (Exam SK0-002), QUE Publishing, Indianapolis, 2006, p. 464.