Testosterone is a

Options

A. Lipid
B. Protein
C. Polysaccharide
D. Steroid

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the nature of testosterone, specifically whether it is a lipid, protein, polysaccharide, or steroid.

2. **Identifying Testosterone**: Testosterone is a hormone produced primarily in the testes in males. It is important to recognize that hormones can be classified based on their chemical structure.

3. **Classifying Hormones**: Hormones can be broadly classified into different categories:
- **Steroid Hormones**: These are derived from cholesterol and are lipid-soluble. Examples include testosterone, estrogen, and cortisol.
- **Protein Hormones**: These are made up of amino acids and are water-soluble. Examples include insulin and growth hormone.
- **Polysaccharides**: These are complex carbohydrates and are not typically classified as hormones.
- **Lipid**: While steroid hormones are lipid-soluble, the term "lipid" generally refers to a broader category of organic compounds.

4. **Determining the Correct Classification**: Given that testosterone is derived from cholesterol and is lipid-soluble, it is classified as a steroid hormone.

5. **Conclusion**: Therefore, the correct answer to the question "Testosterone is a" is that it is a **steroid**.

**Final Answer**: Testosterone is a steroid.

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