Assertion` :-` Progressive degeneration of sekeletal muscle mostly due to genetic disorder, is muscular dystrophy.
Reason `:-` Rapid spasms in muscle due to low `Ca^(++)` in body fluid, is tetany.

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

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Progressive degeneration of skeletal muscle mostly due to genetic disorder, is muscular dystrophy."
- This statement is true. Muscular dystrophy is indeed a group of genetic disorders characterized by progressive weakness and degeneration of the skeletal muscles.

2. **Understanding the Reason**:
- The reason states that "Rapid spasms in muscle due to low Ca^(++) in body fluid, is tetany."
- This statement is also true. Tetany is a condition characterized by muscle spasms, which can occur due to low levels of calcium in the blood.

3. **Analyzing the Relationship**:
- The assertion and the reason are both true. However, we need to determine if the reason correctly explains the assertion.
- Muscular dystrophy and tetany are different conditions. Muscular dystrophy is a genetic disorder leading to muscle degeneration, while tetany is related to calcium levels affecting muscle contractions. Therefore, the reason does not explain the assertion.

4. **Conclusion**:
- Since both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion, the correct option is: "Both assertion and reason are true, but reason is not the correct explanation of the assertion."

### Final Answer:
The correct option is: **Both assertion and reason are true, but reason is not the correct explanation of the assertion.**

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