_______ is widely used to prevent heart attacks

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for a substance that is widely used to prevent heart attacks.

2. **Recall Relevant Information**: One of the most commonly used medications for preventing heart attacks is aspirin.

3. **Understand the Properties of Aspirin**: Aspirin is classified as a non-narcotic analgesic and antipyretic drug.
- Non-narcotic means it is not addictive.
- Analgesic means it helps relieve pain.
- Antipyretic means it helps reduce fever.

4. **Mechanism of Action**: Aspirin works by thinning the blood. It does this by preventing platelets from coagulating (clumping together), which is crucial because blood clots can lead to heart attacks.

5. **Conclusion**: Therefore, the answer to the question is "Aspirin."

**Final Answer**: Aspirin is widely used to prevent heart attacks.

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