Final answer:
In the context of physics, for an object in motion with constant acceleration, the rate of change of velocity is consistent and the distance traveled is proportional to the square of the time, but the object does not necessarily have to move in a straight line or be subject to zero net force.
Step-by-step explanation:
The question is about motion with constant acceleration in the context of Physics.
Option (A) The rate of change of velocity is constant, is correct because with constant acceleration the velocity changes at a steady rate over time. This means if an object is accelerating at a constant rate, its velocity increases by the same amount every second.
Option (B) indicates an object must be subject to zero net force, which is inaccurate in the context of constant acceleration. Instead, this describes an object in uniform motion, where it moves at a constant velocity due to no net force acting on it, as per Newton's first law of motion.
Regarding Option (C), it's true that the distance traveled is proportional to the square of the time when an object is under constant acceleration, according to the kinematic equation d = 1/2 at^2, where 'd' represents distance, 'a' is the acceleration, and 't' is time.
Option (D) suggests that the object must move in a straight line; however, constant acceleration does not inherently mean the motion must be straight. An object can have constant acceleration while moving in a curved path, such as in circular motion.