Final answer:
An object with zero acceleration is one moving with constant velocity or at rest, indicating no change in speed or direction and resulting in balanced forces acting upon it.
Step-by-step explanation:
The object with zero acceleration is an object moving with constant velocity. When an object is moving with constant velocity, it means both its speed and direction are constant, and thus it does not experience a change in velocity, which is what acceleration is. This is in accordance with Newton's second law of motion where if the acceleration is zero, the net external force must also be zero, indicating that the object is in equilibrium. It does not mean that no forces are acting upon it, rather that the forces are balanced. An object at rest also has zero acceleration as long as it remains at rest, although in the context of the initial question, the term 'constant velocity' most accurately captures the concept of zero acceleration.