Certa in B v itamins are

Options

A. Enzymes
B. Coenzymes
C. Hormone
D. Digestive substance

Answer

**Step-by-Step Solution:**

1. **Identify the B Vitamins**: The B vitamins include B1 (Thiamine), B2 (Riboflavin), B3 (Niacin), B5 (Pantothenic acid), B6 (Pyridoxine), B7 (Biotin), B9 (Folic acid), and B12 (Cobalamin).

2. **Understand Their Solubility**: All B vitamins are water-soluble, which means they dissolve in water and are not stored in the body. This characteristic is important for their absorption and utilization.

3. **Functions of B Vitamins**: B vitamins serve various functions in the body, primarily acting as cofactors for enzymatic reactions. They are essential for converting food into energy and are involved in the synthesis of neurotransmitters and red blood cells.

4. **Cofactors and Coenzymes**: B vitamins often act as coenzymes, which are non-protein molecules that assist enzymes in catalyzing reactions. They can also serve as precursors for these coenzymes.

5. **Conclusion**: Given that B vitamins are primarily known for their role as coenzymes and their involvement in enzymatic processes, the correct categorization of B vitamins is that they act as coenzymes.

6. **Final Answer**: Therefore, the answer to the question "Certain B vitamins are" is that they are coenzymes.

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