Which is the correct statement about birth control pills?

Options

A. Contain estrogen only
B. Contain progesterone only
C. Contain a mixture of estrogen and progesterone derivatives
D. Progesterone enhances ovulation

Explanation

### Step-by-Step Solution:

1. **Understanding Birth Control Pills**:
- Birth control pills are chemical substances used to prevent pregnancy in women. They work by altering hormonal levels in the body.

2. **Analyzing the Options**:
- **Option 1**: "Contains estrogen only" - This statement is incorrect because most birth control pills do not contain estrogen alone; they often contain a combination of hormones.
- **Option 2**: "Contains progesterone only" - This statement is also incorrect for the same reason as option 1; most pills include more than just progesterone.
- **Option 3**: "Contain a mixture of estrogen and progesterone derivatives" - This statement is correct, as many birth control pills are formulated with both synthetic estrogen and progesterone derivatives.
- **Option 4**: "Progesterone enhances ovulation" - This statement is false because progesterone actually suppresses ovulation, not enhances it.

3. **Conclusion**:
- The correct statement about birth control pills is **Option 3**: "Contain a mixture of estrogen and progesterone derivatives."

4. **Examples of Birth Control Pills**:
- Norethindrone and Novestrol are examples of birth control pills that contain a combination of these hormones.

### Final Answer:
The correct statement about birth control pills is: **Option 3 - Contain a mixture of estrogen and progesterone derivatives.**

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