Final answer:
At the highest point, a thrown baseball has maximum displacement, with its velocity at zero and constant acceleration due to gravity.
Step-by-step explanation:
When a baseball is thrown from the outfield toward the catcher and reaches its highest point, the correct statement is that the ball has the maximum displacement. At this point, the velocity of the ball is zero because it has momentarily stopped moving upward before starting to fall back down. The acceleration due to gravity is constant throughout the motion, so it is not at a maximum at the highest point. Kinetic energy is highest when the ball's velocity is greatest, which is not at the peak of its trajectory.