What does Newton's First Law state?

Newton's First Law, often referred to as the Law of Inertia, encompasses several important concepts regarding the behavior of objects in motion and at rest. The law states that an object will remain at rest or continue to move at a constant velocity unless acted upon by an unbalanced force. This includes the understanding that if an object is at rest, it will stay at rest until some force causes it to move, and if it is in motion, it will maintain its state of motion unless a force acts upon it.

Thus, the statement that an object at rest stays at rest captures one aspect, while the assertion that an object in motion stays in motion reflects another. Together, they form a complete picture of how forces impact the state of an object, which is why the correct answer encompasses all of these statements. Therefore, recognizing that all these principles are integral to the law demonstrates a fundamental understanding of inertia in physics.