Assertion : Females not participate in the determination of the sex of baby .
Reason : Human male is heterogametic .

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

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that females do not participate in the determination of the sex of the baby.
- In humans, females have two X chromosomes (XX), which means all their gametes (eggs) carry an X chromosome.

2. **Understanding the Reason**:
- The reason states that the human male is heterogametic.
- Males have one X and one Y chromosome (XY), which means they produce two types of gametes: 50% carry an X chromosome (gynosperms) and 50% carry a Y chromosome (androsperms).

3. **Linking the Assertion and Reason**:
- The sex of the baby is determined by the combination of the gametes from both parents.
- Since the female can only contribute an X chromosome, the sex of the baby depends on whether the male contributes an X (resulting in a female baby) or a Y (resulting in a male baby).
- Therefore, the male's heterogametic nature (having both X and Y chromosomes) is what allows him to determine the sex of the baby.

4. **Conclusion**:
- Both the assertion and the reason are true.
- The reason correctly explains the assertion, as the male's heterogametic condition is what leads to the determination of the baby's sex.

5. **Final Answer**:
- The correct answer is that both the assertion and reason are true, and the reason is the correct explanation for the assertion.