Why is your laptop screen black?

Your laptop screen was working properly yesterday, but now the display doesn’t show anything. When booting up the laptop, you notice that the LCD display backlight isn’t turning on at all and you can see a faint image appearing on the LCD panel. Connectivity to an external monitor works normally. What is the most likely problem?

A) The LCD inverter is bad

B) The LCD panel is faulty

C) The LCD panel open/close switch is faulty

D) The operating system software is automatically selecting the external monitor instead of the internal LCD display.