Which of the following is an expression of Newton's second law? A. The acceleration of an object is determined by its mass and the net force acting on it. O O B. Objects at rest tend to stay at rest and objects in motion tend to stay in motion unless acted on by an unbalanced force. C. Objects at rest tend to stay at rest, and objects in motion tend to slow down until they come to rest. D. Every force is paired with an equal and opposite force.​