A: Sarcomere is the basic unit of muscles.
R: Cell is the basic unit of life.

Options

A. IF both Assertion & Reason are true and the reason is the correct explanation of the assertion , then mark
B. If Both Assertion & Reason are true but the reason is not the correct exlanation of the assertion then mark
C. IF Assertion is true statement but Reason is false then mark
D. If both Assertion and Reason are false statements then joint

Answer

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

### Step 1: Analyze the Assertion
- The assertion states that "Sarcomere is the basic unit of muscles."
- This statement is **true**. Sarcomeres are indeed the smallest functional units of muscle fibers, responsible for muscle contraction.

### Step 2: Analyze the Reason
- The reason states that "Cell is the basic unit of life."
- This statement is also **true**. Cells are recognized as the fundamental building blocks of all living organisms, serving as the basic structural and functional units of life.

### Step 3: Determine the Relationship
- Now, we need to determine if the reason provided is the correct explanation for the assertion.
- While both statements are true, the reason (about cells) does not explain why sarcomeres are the basic unit of muscles. Sarcomeres are specific to muscle tissue, while the reason pertains to all living organisms.

### Step 4: Conclusion
- Since both the assertion and the reason are true, but the reason does not explain the assertion, we conclude that the correct option is:
- **Option B**: Both assertion and reason are true, but reason is not the correct explanation of the assertion.

### Final Answer
The correct option is **B**.

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