Which of the following is the MOST likely cause of the issue?

A user with a CRT monitor notes that there is a discolored area in a portion of their screen.
Which of the following is the MOST likely cause of the issue?

A.
Bad video card

B.
The video card drivers need to be upgraded

C.
Bad monitor

D.
The screen needs to be degaussed

Explanation:

Reference:
http://www.wikihow.com/Degauss-a-Computer-Monitor