When a muscle contracts suddenly and powerfully, it results in 

Options

A. Strain
B. Stress
C. Sprain
D. Spasm

Answer

**Step-by-Step Solution:**

1. **Understanding Muscle Contraction**: When a muscle contracts, it can do so in various ways. A sudden and powerful contraction can lead to different outcomes depending on the context and severity of the contraction.

2. **Analyzing the Options**:
- **Spasm**: This refers to an involuntary contraction of a muscle. It is often caused by factors like dehydration or overexertion. However, spasms are not typically associated with a sudden powerful contraction that is voluntary.
- **Sprain**: A sprain involves injury to ligaments around a joint, usually due to trauma or excessive force that displaces the joint. This does not directly relate to muscle contraction.
- **Stress**: Stress can refer to the tension experienced by muscles but does not specifically describe the result of a sudden powerful contraction.
- **Strain**: A strain occurs when a muscle or tendon is stretched or torn due to excessive force. This is the most relevant option when considering a sudden and powerful muscle contraction.

3. **Conclusion**: Based on the analysis, the correct answer is that when a muscle contracts suddenly and powerfully, it results in a **strain**.

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