Assertion (A): Saheli is considered as an improved form of contraceptive for human females.
Reason ( R) : It is a non-steroidal preparation and is once a week pill.

Options

A. Both assertion (A) and reason ( R) are true and reason ( R) is the correct explanation of assertion (A).
B. Both assertion (A) and reason ( R) are true but reason ( R) is not the correct explanation of assertion (A).
C. Assertion (A) is true but reason ( R) is false.
D. Assertion (A) is false but reason ( R) is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A):** The assertion states that "Saheli is considered as an improved form of contraceptive for human females." This means that Saheli is recognized for its effectiveness and advantages over other contraceptive methods.

2. **Understanding the Reason (R):** The reason provided is that "It is a non-steroidal preparation and is a once-a-week pill." This indicates that Saheli has specific characteristics that contribute to its classification as an improved contraceptive.

3. **Evaluating the Assertion:** Saheli is indeed an oral contraceptive that is considered improved because it has a higher contraceptive efficacy and fewer side effects compared to traditional hormonal contraceptives.

4. **Evaluating the Reason:** The fact that Saheli is non-steroidal is significant because non-steroidal contraceptives tend to have fewer side effects compared to steroidal ones. Additionally, the convenience of taking the pill once a week makes it more user-friendly.

5. **Conclusion:** Both the assertion and the reason are correct. The reason explains why Saheli is considered an improved contraceptive, as its non-steroidal nature and the once-a-week dosage contribute to its effectiveness and reduced side effects.

6. **Final Answer:** Therefore, the correct option is: "Both assertion and reason are correct, and reason explains assertion correctly."

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