Assertion : The testes are situated outside the abdominal cavity within scrotum .
Reason : Lower temperature for the testis is necessary for spermatogenesis.

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

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "The testes are situated outside the abdominal cavity within the scrotum." This is a factual statement about the anatomical location of the testes in the male reproductive system.

2. **Understanding the Reason**: The reason provided is "Lower temperature for the testis is necessary for spermatogenesis." This statement explains why the testes are located in the scrotum, as spermatogenesis (the process of sperm formation) requires a temperature that is slightly lower than the normal body temperature.

3. **Evaluating the Truth of the Assertion**: The assertion is true. The testes are indeed located outside the abdominal cavity in the scrotum, which is a pouch of skin that helps regulate their temperature.

4. **Evaluating the Truth of the Reason**: The reason is also true. Spermatogenesis occurs optimally at a temperature that is about 2-3 degrees Celsius lower than the core body temperature, which is why the testes are located in the scrotum, allowing them to maintain this lower temperature.

5. **Determining the Relationship**: Since both the assertion and the reason are true, and the reason correctly explains why the assertion is true, we conclude that the reason is a correct explanation of the assertion.

6. **Selecting the Correct Option**: Based on the evaluation, the correct option is that both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

**Final Answer**: The correct option is: Both the assertion and reason are true, and the reason is a correct explanation of the assertion.

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