An aircraft pilot uses a simulation software program on his pc to demonstrate a new mission assigned to him. He uses a special joystick to train to fly the aircraft through a specific track. Each time he gets out of the specific track, a red lamp lights out. The sensor of the control :system that represents this process is

$$:

The special joystick $,.a$

None of these choices is true $.$b

The desired track of the aircraft $.$c

Flying the aircraft through a specific track $.$d

All of these choices are true $.$e

The pilot $.$f

The actual track of the aircraft $,.g$

The red lamp light $,.h$