Final answer:
At the highest point of the loop, the pilot's apparent weight is decreased because both the gravitational force and the normal force exerted by the seat are acting in the same direction toward the center of the loop, leading to a decreased normal force.
Step-by-step explanation:
When the pilot is at the highest point of the loop, his apparent weight would be decreased. This is because the centripetal force needed to keep the pilot moving in a circular path is provided by the gravitational force and the normal force exerted by the seat of the airplane. At the top of the loop, the gravitational force is acting downwards, and as the pilot is inverted at this point, the normal force from the seat also acts downwards, toward the center of the loop. This means that both forces are in the same direction and the normal force is less than the gravitational force, which causes the decrease in apparent weight that the pilot feels, making the correct answer B) Decreased.