Assertion: Iodine deficiency may lead to irregular menstrual cycle
Reason: Estrogen and progesterone level becomes low

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

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

### Step 1: Understand the Assertion
The assertion states that "Iodine deficiency may lead to irregular menstrual cycle."
- Iodine is essential for the production of thyroid hormones. A deficiency in iodine can lead to low levels of thyroid hormones, which can affect various bodily functions, including the menstrual cycle.

### Step 2: Understand the Reason
The reason states that "Estrogen and progesterone levels become low."
- While it is true that thyroid hormones can influence the menstrual cycle, the assertion does not directly state that the irregular menstrual cycle is due to low estrogen and progesterone levels. Instead, it is primarily due to the effects of low thyroid hormone levels.

### Step 3: Evaluate the Relationship
- The assertion is true because iodine deficiency can indeed lead to irregular menstrual cycles.
- The reason is misleading because it implies that the irregularity is directly due to low levels of estrogen and progesterone, which is not the primary cause. The irregular cycle is more directly related to low thyroid hormone levels.

### Conclusion
Based on the analysis:
- The assertion is true.
- The reason is false.

Thus, the correct answer is: **Assertion is true but reason is false.**

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