(A):Body may be moving with uniform speed and non uniform acceleration
(R ):A body may have uniform velocity and nonzero acceleration . 1)Both A and R are true and R is correct explanation of A 2)Both A and R are true R is not the correct explanation of A 3)A is true R is False 4)Both A and R are false

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) given in the problem.

### Step 1: Analyze the Assertion (A)
The assertion states: "A body may be moving with uniform speed and non-uniform acceleration."

- **Uniform Speed**: This means that the speed of the body remains constant over time. However, acceleration refers to the change in velocity over time.
- **Non-uniform Acceleration**: This means that the acceleration of the body is changing, which implies that the velocity is changing as well.

Since a body can have a constant speed while its direction changes (like in circular motion), it can have non-uniform acceleration. Therefore, the assertion is **true**.

### Step 2: Analyze the Reason (R)
The reason states: "A body may have uniform velocity and non-zero acceleration."

- **Uniform Velocity**: This means that both the speed and direction of the body are constant.
- **Non-zero Acceleration**: This means that there is a change in velocity, which can either be an increase or decrease in speed or a change in direction.

If a body has uniform velocity, it cannot have non-zero acceleration because acceleration indicates a change in velocity. Therefore, the reason is **false**.

### Conclusion
Based on the analysis:
- Assertion (A) is true.
- Reason (R) is false.

Thus, the correct option is **3) A is true, R is false**.

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