Question

You are throwing a ball straight up in the air. At the highest point, the ball's.....

acceleration is nonzero, but its velocity is zero.
velocity and acceleration are both nonzero.
velocity is nonzero but its acceleration is zero.
velocity and acceleration are zero.​

Answer 1

velocity and acceleration are zero.​

Answer 2

When a ball is thrown exactly straight up in the air, at its highest point, velocity and acceleration are zero.​

This is because, at the ball's highest point, the ball is not moving in any direction meaning the vector quantity (direction and magnitude) is zero for both velocity and acceleration.