One of the legal methods of birth control is

Options

A. By having coitus at the time of day break
B. By a premature ejaculation during coitus
C. Abortion by taking an appropriate medicine
D. By abstaining from coitus from day 10 to 17 of the menstrual cycle

Explanation

**Step-by-Step Solution:**

1. **Understanding Birth Control Methods**: The question asks for a legal method of birth control. It's essential to differentiate between legal and illegal methods.

2. **Evaluating Coitus Timing**: The first method mentioned is having coitus at daybreak. This method does not effectively prevent pregnancy, making it an incorrect choice.

3. **Considering Premature Ejaculation**: The second method involves premature ejaculation during coitus. Similar to the first method, this does not provide a reliable means of birth control, hence it is also incorrect.

4. **Analyzing Abortion**: The third method discussed is abortion through medication. While abortion can terminate a pregnancy, it is considered an illegal method of birth control in many regions, including India. Therefore, this option is incorrect.

5. **Reviewing the Menstrual Cycle**: The fourth method suggests abstaining from coitus from day 10 to day 17 of the menstrual cycle. Understanding the menstrual cycle is crucial here. Ovulation typically occurs around day 14, meaning that engaging in coitus during this time could lead to fertilization.

6. **Conclusion**: Abstaining from coitus between days 10 to 17 is a legal method of birth control because it minimizes the chances of sperm meeting an ovum, thus preventing pregnancy.

7. **Final Answer**: The correct answer to the question is abstaining from coitus from day 10-17 of the menstrual cycle.

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