Question

what is needed for acceleration of an object to occur?
change in position
change in velocity
change in force
change in direction

Explanation:

Acceleration is defined as the rate of change of velocity. A change in velocity (either in magnitude or direction) is required for acceleration to occur. A change in position is related to displacement, a change in force is related to Newton's second - law, and a change in direction is one aspect of a change in velocity.

Answer:

change in velocity