In most of the mammals the testes are situated outside the abdominal cavity because

Options

A. Sperms produced in scrotal sac are more in number
B. Sperms produced in abdominal cavity are provided with less motility
C. Sperms produced in scrotal sac require lesser temperature for their best fertilization capacity
D. Sperms produced in scrotal sac are bigger

Explanation

**Step-by-Step Solution:**

1. **Understanding the Location of Testes**: In most mammals, the testes are located in the scrotal sac, which is situated outside the abdominal cavity.

2. **Importance of Temperature**: The production of sperm requires a specific temperature that is lower than the normal body temperature. This is crucial because higher temperatures can adversely affect sperm production and viability.

3. **Role of the Scrotal Sac**: The scrotal sac provides an environment that maintains a temperature lower than that of the body. This cooler temperature is essential for optimal sperm production and their fertilization capacity.

4. **Conclusion**: Therefore, the primary reason why the testes are located outside the abdominal cavity in most mammals is that the sperm produced in the scrotal sac requires a lower temperature for their best fertilization capacity.

5. **Correct Answer**: The correct option is that "sperms produced in scrotal sac require lesser temperature for their best fertilization capacity."

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