Proteins consist of-

Options

A. Carbon, hydrogen, chlorine, sulfur
B. Carbon, hydrogen, oxygen, nitrogen
C. Carbon, manganese, phosphorus, nitrogen
D. Carbon, iodine, oxygen and inorganic phosphate

Explanation

**Step-by-Step Solution:**

1. **Understanding the Composition of Proteins:**
- Proteins are complex biomolecules that play crucial roles in the body, including structural, functional, and regulatory functions. They are primarily made up of smaller units called amino acids.

2. **Identifying the Elements in Proteins:**
- The basic elements that make up proteins include:
- Carbon (C)
- Hydrogen (H)
- Oxygen (O)
- Nitrogen (N)
- Sulfur (S) (in some amino acids)

3. **Amino Acids as Building Blocks:**
- Proteins are polymers formed from amino acids. Each amino acid consists of:
- A central carbon atom
- An amino group (-NH2)
- A carboxyl group (-COOH)
- A hydrogen atom
- A variable side chain known as the R group, which determines the specific properties of each amino acid.

4. **Common Compositions of Proteins:**
- While proteins can contain various elements, the most consistent and significant elements found in all proteins are carbon, hydrogen, oxygen, and nitrogen. Sulfur is present in some amino acids but is not a universal component of all proteins.

5. **Conclusion:**
- Based on the analysis, the correct answer to the question "Proteins consist of-" is:
- Carbon, Hydrogen, Oxygen, and Nitrogen.

**Final Answer:**
Proteins consist of carbon, hydrogen, oxygen, and nitrogen.

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