Assertion : A body can be at rest even when it is under the action of may number of external forces
Reason : Because vector sum of the all external forces is zero .

Options

A. If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.
B. If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.
C. If Assertion is Trie but the Reason is False.
D. If both Assertion `&` Reason are false

Explanation

To solve the given assertion and reason question, we will analyze both statements step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that a body can be at rest even when it is under the action of many external forces.
- This is true because a body can remain in a state of rest if the forces acting on it are balanced.

2. **Understanding the Reason**:
- The reason provided states that the vector sum of all external forces is zero.
- This is also true because, according to Newton's First Law of Motion, a body at rest will remain at rest if the net external force acting on it is zero.

3. **Connecting the Assertion and Reason**:
- If multiple forces are acting on a body and their vector sum is zero, then the body is in equilibrium.
- In equilibrium, the body does not experience any net force, which means it can remain at rest.

4. **Conclusion**:
- Since both the assertion and the reason are true, and the reason correctly explains the assertion, we conclude that the statement is valid.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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