Assertion :- A woman usually does not conceive during the lactation period.
Reason:- The hormone "Prolactin" stimulate the growth of milk glands during pregnancy.

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.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that a woman usually does not conceive during the lactation period. This is based on the natural biological processes that occur after childbirth.

2. **Defining the Lactation Period**: The lactation period refers to the time after childbirth when a mother breastfeeds her infant. During this time, hormonal changes occur that can inhibit ovulation.

3. **Explaining the Mechanism**: During lactation, the hormone prolactin is released in higher amounts. Prolactin is responsible for stimulating milk production and also plays a role in suppressing ovulation. This is why the chances of conception are significantly reduced during this period.

4. **Duration of Effectiveness**: The natural contraceptive effect of lactation is most effective for up to six months postpartum, provided the mother is exclusively breastfeeding.

5. **Analyzing the Reason**: The reason given states that prolactin stimulates the growth of milk glands during pregnancy. While this is true, it does not directly explain why a woman does not conceive during lactation. Prolactin's role in milk production is related to breastfeeding rather than directly preventing conception.

6. **Conclusion**: Both the assertion and reason are true statements. However, the reason does not adequately explain the assertion. Therefore, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

### Final Answer:
Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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