A Domain.com has a computer that has become sluggish after months of use. What should the Domain.com technician do to improve performance?

A.
Add more RAM.

B.
Upgrade the CPU.

C.
Defragment the hard drive.

D.
All of the above.

Explanation:
Due to read a write processes on a hard drive, fragmentation of data occurs after time. This causes slower read/writes and can be resolved by regularly deframenting the hard drive.
Incorrect Answers
A, B, D: Upgrading the RAM or CPU would increase system performance but a fragmented hard disk is best optimized by deframentation.
References:
David Groth and Dan Newland, A+ Complete Study Guide (2nd Edition), Sybex Inc, Alameda, CA, 2001, pp. 74-86, 114-116, 172-177.