A

Step 1: Understand the scenario. The body starts from a height and follows a loop. At the highest point of the loop, the centripetal force is required to keep the body in circular motion.
Step 2: Analyze the forces acting on the body at the highest point. The only force acting on the body at this point is gravity (weight). The normal force is zero, as the body does not exert any pressure on the loop.
Step 3: Relate the forces to centripetal force. At the highest point, the gravitational force provides the necessary centripetal force required for circular motion:
$$mg = \frac{mv^2}{R}$$ where $m$ is mass, $g$ is acceleration due to gravity, $v$ is velocity at the highest point, and $R$ is the radius of the loop.
Step 4: Determine centrifugal force. Centrifugal force is a fictitious force experienced in a rotating frame of reference. However, in this case, the body experiences an apparent force pushing it outward as it moves in a circular path.
Step 5: Conclusion. The body slipping down the chute at the highest point does not exert pressure due to insufficient gravitational force that cannot provide enough centripetal force required to remain in contact with the loop. Therefore, the centrifugal force acts on the body itself at that moment.