Here we have to memorize the Newtons laws of motion. In his first law of motion of an object he has stated that If the net force acting on a body is zero then the body is at rest or moving in a straight line at an uniform velocity.
So by this law we can conclude that the answer as d)
The answer would be d. If the net Force on an object is zero, it could be at rest, but it could also be in motion with constant velocity.
The answer is d.
If the net force on an object is zero, it could be either rest or in a mortion with constant velocity.