Assertion: The terms action and reaction in the third law of motion stand for simultaneous mutual force between a pair of bodies.
Reason: In this context action always precede or cause reaction.

Options

A. Both assertion and reason are true and reason is the correct explanation of assertion.
B. Both assertion and reason are true and reason is the not correct explanation of assertion.
C. The assertion is true but reason is false
D. Both assertion and reason are false.

Explanation

To analyze the given question, we need to evaluate both the assertion and the reason provided in the context of Newton's Third Law of Motion.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "the terms action and reaction in the third law of motion stand for simultaneous mutual force between a pair of bodies."
- According to Newton's Third Law of Motion, for every action, there is an equal and opposite reaction. This means that when one body exerts a force on another body (action), the second body exerts an equal force in the opposite direction back on the first body (reaction).
- These forces occur simultaneously; they do not happen one after the other. Thus, the assertion is **true**.

2. **Understanding the Reason**:
- The reason states that "in this context action always precedes or causes reaction."
- This statement implies a sequence where the action comes first and the reaction follows. However, according to Newton's Third Law, action and reaction occur at the same time, making this statement misleading.
- Therefore, the reason is **false**.

3. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer to the question is that the assertion is true, but the reason is false.

### Final Answer:
The assertion is true, but the reason is false.

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