Final answer:
The motion of the student on the Ferris wheel is best described as the velocity changing because the direction is changing.
Step-by-step explanation:
The best statement that describes the motion of the student on the Ferris wheel is A) The velocity is changing because the direction is changing. On a Ferris wheel, the student is undergoing uniform circular motion, which involves a constant speed but a changing direction at each point of the motion.
In a uniform circular motion, like the motion of the Ferris wheel, the speed remains constant but the direction of the velocity changes continuously. As the Ferris wheel rotates, the student's velocity vector continually points in a different direction even though the speed remains the same. Therefore, the velocity is changing.