Assertion: Muscle fibre is a syncitium.
Reason: Muscle fibre has a large number of parallelly arraaged myofilaments in the sarcoplasm.

Options

A. If both assertion and reason are ture and reason is the corect explanation of assertion
B. If both assertion and reason are ture but reson is not the correct explanation of assertion
C. If assertion is true reason is false
D. If both assertion and reason are false

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Muscle fibre is a syncytium." This means that muscle fibers contain multiple nuclei rather than a single nucleus, which is characteristic of typical cells.

2. **Analyzing the Structure of Muscle Fibers**: Muscle fibers, particularly skeletal muscle fibers, are indeed syncytial in nature. They are formed by the fusion of multiple myoblasts during development, resulting in a long, multinucleated cell. This structure is essential for the function of skeletal muscles, which are responsible for voluntary movements.

3. **Understanding the Reason**: The reason given is "Muscle fibre has a large number of parallelly arranged myofilaments in the sarcoplasm." This statement is also correct. Muscle fibers contain myofilaments (actin and myosin) that are arranged in parallel, which is crucial for muscle contraction and gives the muscle its striated appearance.

4. **Evaluating the Relationship**: While both the assertion and the reason are correct, the reason does not explain why muscle fibers are considered a syncytium. The presence of multiple nuclei is due to their developmental origin, not directly because of the arrangement of myofilaments.

5. **Conclusion**: Therefore, the correct answer is that both statements are true, but the reason is not a valid explanation for the assertion.

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

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