[A]: The "balloon pump" is used to assist the heart.
[R]: Balloon is used when heart is removed from the body.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

### Step-by-Step Solution

1. **Understanding the Assertion (A)**: The assertion states that the "balloon pump" is used to assist the heart. This is correct as the balloon pump, also known as an intra-aortic balloon pump (IABP), is a medical device used to support patients with heart conditions by improving blood flow and reducing the workload on the heart.

2. **Understanding the Reason (R)**: The reason states that the balloon is used when the heart is removed from the body. This is incorrect. The balloon pump is not designed to function when the heart is removed; it is used to assist the heart while it is still in the body.

3. **Evaluating the Relationship**: Since the assertion is true and the reason is false, we need to determine if the reason correctly explains the assertion. In this case, it does not, as the balloon pump assists the heart rather than being a substitute when the heart is absent.

4. **Conclusion**: Based on the evaluation, the assertion is true, but the reason is false. Therefore, the correct answer is that the assertion is true, but the reason is not a correct explanation of the assertion.

### Final Answer
- The assertion (A) is true.
- The reason (R) is false.
- The correct answer is that the assertion is true, but the reason is false.

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