Final answer:
The Display Control Panel is used to select NAV SRC for the PFD. It is a critical component for a pilot to manage navigation data sources while flying.
Step-by-step explanation:
The control panel used to select NAV SRC (Navigation Source) for display on the Primary Flight Display (PFD) is b) Display Control Panel. The Display Control Panel allows pilots to select various data sources for their navigation displays including the PFD. This capability is crucial for ensuring that the pilots are navigating with the correct information and can switch between different navigational aids such as GPS, VOR, or ILS accordingly.