Answer:
C. An object at rest remains at rest and an object in motion remains in motion at a constant speed and in a straight line, unless acted upon by an unbalanced force.
Explanation:
In essence, Newton's first law of motion states that an object at rest won't move unless an outside force causes it to move. Similarly, an object moving at a constant speed will continue moving at that same speed indefinitely, unless an outside force causes it to change speed.
