A: Lactational amenorrhoea is one of the natural method of birth control.
R: High level of prolactin inhibits the secretion of gonadotropins.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reasons is not the correct expalanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4).

Answer

### Step-by-Step Solution

1. **Understanding the Assertion**: The assertion states that "lactational amenorrhea is one of the natural methods of birth control."
- **Explanation**: Lactational amenorrhea refers to the absence of menstrual cycles during the period of breastfeeding. This natural method of birth control relies on the physiological changes that occur in a woman's body during lactation.

2. **Understanding the Reason**: The reason provided is that "high levels of prolactin inhibit the secretion of gonadotropins."
- **Explanation**: Prolactin is a hormone produced by the anterior pituitary gland that plays a key role in milk production. During breastfeeding, prolactin levels increase, which in turn inhibits the secretion of gonadotropins (FSH and LH) from the pituitary gland.

3. **Linking the Assertion and Reason**:
- **Assertion Validity**: Since lactational amenorrhea prevents ovulation due to the absence of gonadotropins, it is indeed a natural method of birth control.
- **Reason Validity**: The reason is true because high levels of prolactin do inhibit gonadotropin secretion, which prevents ovulation.

4. **Conclusion**: Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
Both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

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