What must be removed from the new LCD panel before reassembling a system?

The correct choice is the protective cover. When dealing with a new LCD panel, it typically comes with a protective cover to shield the screen from scratches and damage during handling and transport. This protective cover must be removed before reassembling the system to ensure that the panel is clean and free from any obstructions that could affect its functionality and visibility.

If the protective cover is left on, it can cause issues such as distortion in the display, improper fit within the frame, or even potential overheating if it traps heat. Ensuring the screen is bare before installation is crucial for optimal performance and long-term reliability.

Wiring harnesses and mounting brackets are components integral to the functioning and securing of the LCD panel within the system. Removing them would not be appropriate or necessary for the assembly process, as they are essential for connecting the panel and ensuring it is safely held in place. The screen protector, although it may be applied to some surfaces of the panel, is not as universally applicable as the protective cover and may not even be a standard part of the LCD panel setup.