A tennis ball bounces higher on a hill than on a field because Earth’s gravitational acceleration decreases on mountains, which is; option [C]. Gravitational acceleration is weaker at higher altitudes due to the greater distance from Earth’s center, resulting in less downward force acting on the ball. This reduced gravitational force allows the ball to rebound higher after each bounce compared to when it is on a field at lower elevation. Options A and B are not relevant to the increase in bounce height on a hill, as air pressure and the weight of the ball do not directly affect its bounce height in this context. Therefore, the primary reason for the higher bounce on a hill is the decrease in Earth’s gravitational acceleration at higher elevations, enabling the ball to rebound more effectively against the opposing force of gravity. Consequently, option C accurately explains the phenomenon observed when a tennis ball is bounced on a hill compared to a field.