What causes a moving body to resist a change in its state of motion?

Options

A. Its mass
B. Its speed
C. Its inertia
D. Its weight

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Motion**: A moving body is one that is in motion, meaning it is changing its position with respect to time.

2. **Change in State of Motion**: When we talk about a change in the state of motion, we refer to any alteration in the velocity of the body, which can include speeding up, slowing down, or changing direction.

3. **Inertia Defined**: The property that causes a moving body to resist changes in its state of motion is known as inertia. Inertia is the tendency of an object to maintain its current state of motion unless acted upon by an external force.

4. **Role of Inertia**: Inertia means that if a body is moving, it will continue to move at the same speed and in the same direction unless a force (like friction, gravity, or a push) acts on it to change that motion.

5. **Conclusion**: Therefore, the correct answer to the question is that inertia is the property that causes a moving body to resist a change in its state of motion.

**Final Answer**: The property that causes a moving body to resist a change in its state of motion is called inertia.

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