Progesterone is secreted by

Options

A. Carbohydrate
B. Sterioid
C. Protein
D. Sterol.

Answer

**Step-by-Step Solution:**

1. **Identify the Hormone**: The question asks about progesterone, which is a hormone involved in the reproductive system.

2. **Understand the Nature of Progesterone**: Progesterone is classified as a steroid hormone. Steroid hormones are derived from cholesterol and are lipid-soluble.

3. **Identify the Source of Progesterone**: Progesterone is primarily secreted by the ovaries, specifically from a structure called the corpus luteum, which forms after ovulation. Additionally, during pregnancy, the placenta also secretes progesterone.

4. **Review the Options**: The options provided are:
- A. Carbohydrate
- B. Steroid
- C. Protein
- D. Sterol

5. **Select the Correct Answer**: Since progesterone is a steroid hormone, the correct answer is option B: Steroid.

**Final Answer**: Progesterone is secreted by B. Steroid.

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