Assertion : Pili are nonmotile appendages of bacteria.
Reason : Pili take part in conjugation.

Options

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

Explanation

To analyze the assertion and reason provided in the question, we can break it down step by step:

### Step 1: Understand the Assertion
The assertion states that "Pili are nonmotile appendages of bacteria."
- **Explanation**: Pili (singular: pilus) are hair-like structures found on the surface of many bacteria. They are primarily used for attachment to surfaces and other cells, and they do not contribute to the movement of the bacteria.

### Step 2: Understand the Reason
The reason states that "Pili take part in conjugation."
- **Explanation**: Conjugation is a process by which one bacterium transfers genetic material to another through direct contact. Pili play a crucial role in this process, as they help in the attachment of two bacteria, allowing the transfer of genetic material.

### Step 3: Analyze the Relationship Between Assertion and Reason
- The assertion is true: Pili are indeed nonmotile appendages.
- The reason is also true: Pili do participate in the process of conjugation.

### Step 4: Determine the Correctness of the Explanation
While both the assertion and reason are true, the assertion does not provide a complete explanation for the reason. The fact that pili are nonmotile does not negate their role in conjugation; rather, it highlights their function as attachment structures.

### Conclusion
Both the assertion and reason are correct, but the assertion does not explain the reason adequately. Therefore, the correct answer to the question is that both statements are true, but the assertion does not explain the reason.

### Final Answer
Both the assertion and reason are correct, but the assertion does not explain the reason adequately.

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