Answer: A
Step-by-step explanation:
Newton's first law or the law of inertia states that a body would continue to be at rest or in a state of constant motion unless acted upon by an external force. When the ball is held in the player's hand, the ball is at rest and would remain at that state unless the player exerts a force to move the ball. Likewise, once the ball is thrown, it will continue to remain at a straight line in constant motion unless an external force acts upon it to change its course of direction.