Assertion : Bursa fabricii liles on the ventral side of the cloace in birds.
Reason : Bursa fabricii is related with flight adaptation.

Options

A. If both assertion and reason are true and 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 solve the question, we need to evaluate both the assertion and the reason provided.

### Step 1: Analyze the Assertion
- **Assertion**: "Bursa fabricii lies on the ventral side of the cloaca in birds."
- **Evaluation**: The Bursa Fabricii is a lymphoid organ found in birds. It is actually located on the dorsal side of the cloaca, not the ventral side. Therefore, the assertion is **false**.

### Step 2: Analyze the Reason
- **Reason**: "Bursa fabricii is related with flight adaptation."
- **Evaluation**: The Bursa Fabricii is primarily involved in the immune response by producing lymphocytes and antibodies, especially in young birds. It does not have a direct role in flight adaptation. Thus, the reason is also **false**.

### Conclusion
Since both the assertion and the reason are false, the correct answer is that both the assertion and reason are false.

### Final Answer
Both the assertion and reason are false.

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