Here’s the Answer to the Question posted on Facebook
Q. You are troubleshooting a laptop computer that has a dim display. You are unable to adjust the brightness using the function keys. Of the following choices, what is the MOST likely problem?
A. The battery cannot charge
B. The backlight is lit
C. Device is running on battery power
D. Optical drives are disabled
Answer available until May 23, 2016.
See Chapter 8 of the CompTIA A+ Training Kit (ISBN 978-0735662681) by Darril Gibson.