Answer:
A. Technician A only.B.
Explanation: The fuel system of a vehicle is made up of the fuel pump,the fuel filter,the injector or carburettor and the fuel tank. The main function of the fuel system is supply fuel to the engine of a vehicle. In order to check for leakage in the fuel system a small pressure smoke is usually installed in the fuel system.
Nitrogen at low pressure has also been used to check for leakage in the fuel system of a vehicle.