Assertion `:` Myocardial infarction often results from a sudden decrease in coronary blood supply resulting in decreased oxygen supply.
Reason `:` The portion of myocardium with out oxygen supply dies with in few minutes and then referred to as an infarct or myocardial infarction.

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that myocardial infarction often results from a sudden decrease in coronary blood supply, leading to decreased oxygen supply.
- Myocardial infarction, commonly known as a heart attack, occurs when there is a blockage in the coronary arteries that supply blood to the heart muscle.

2. **Evaluating the Truth of the Assertion:**
- This statement is true because a sudden decrease in blood flow (often due to a clot) prevents oxygen from reaching the heart muscle, which is essential for its function.

3. **Understanding the Reason:**
- The reason provided states that the portion of the myocardium without oxygen supply dies within a few minutes and is referred to as an infarct or myocardial infarction.
- The myocardium refers to the muscular tissue of the heart, and when it does not receive oxygen, it can lead to irreversible damage.

4. **Evaluating the Truth of the Reason:**
- This statement is also true. When the heart muscle is deprived of oxygen, it can start to die within minutes, resulting in what is termed an infarct or myocardial infarction.

5. **Determining the Relationship Between Assertion and Reason:**
- While both the assertion and reason are true, the reason does not serve as the correct explanation for the assertion.
- The assertion explains the cause of myocardial infarction (blockage of blood supply), while the reason describes the consequence of that blockage (death of heart muscle due to lack of oxygen).

6. **Conclusion:**
- Therefore, the final answer is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

**Final Answer:**
Both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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