When comparing multiple balls thrown upward, how are their accelerations similar?

The accelerations of multiple balls thrown upward are equal and constant due to the influence of gravity. Regardless of their mass or any other factors, each ball experiences the same gravitational force acting on it, which results in a uniform acceleration downward. This acceleration due to gravity near the Earth's surface is approximately -9.81 m/s² and acts on all objects equally.

As the balls are thrown upward, they decelerate until they reach their peak height, but the rate at which they decelerate is constant, resulting from the constant gravitational acceleration. This concept is a key principle in physics known as the equivalence principle, which states that all objects in free fall experience the same acceleration regardless of their mass. Therefore, the correct answer points to the uniformity of acceleration experienced by all of the balls under the influence of gravity.