Assertion : Intra-uterine devices (IUDs) are very effective contraceptive method.
Reason : IUDs do not allow sperms to enter uterus.

Options

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

Answer

To solve the question, we will analyze the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that "Intra-uterine devices (IUDs) are very effective contraceptive methods."
- This is true. IUDs are widely recognized as effective forms of contraception because they can prevent pregnancy through various mechanisms.

### Step 2: Understand the Reason
The reason states that "IUDs do not allow sperms to enter the uterus."
- This statement is misleading. While IUDs can inhibit sperm movement and prevent fertilization, they do not completely block sperm from entering the uterus. Instead, they create an environment that is unfavorable for sperm survival and movement.

### Step 3: Analyze the Relationship
Now we need to determine if the reason provided is the correct explanation for the assertion.
- The assertion is true, but the reason is not accurately explaining why IUDs are effective. IUDs work by preventing fertilization and implantation, not solely by blocking sperm from entering the uterus.

### Conclusion
Based on the analysis:
- The assertion is true, but the reason is false. Therefore, the correct answer is option 3: "Assertion is true but reason is false."

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