Which one of the following is not an oligosaccharide

Options

A. Insulin
B. Maltose
C. Sucrose
D. Raffinose

Answer

To determine which of the following is not an oligosaccharide, we first need to understand what oligosaccharides are.

### Step-by-Step Solution:

1. **Definition of Oligosaccharides**:
Oligosaccharides are carbohydrates that consist of 2 to 10 monosaccharide units. They can be classified into different types based on the number of monosaccharides they contain.

2. **Analyzing the Options**:
- **Option A: Insulin**:
- Insulin is a protein hormone produced by the pancreas. It is not a carbohydrate and does not consist of monosaccharide units. Therefore, insulin is not an oligosaccharide.
- **Option B: Maltose**:
- Maltose is a disaccharide made up of two glucose molecules. Since it consists of two monosaccharide units, it qualifies as an oligosaccharide.
- **Option C: Sucrose**:
- Sucrose is also a disaccharide, composed of one glucose and one fructose molecule. As it contains two monosaccharide units, it is classified as an oligosaccharide.
- **Option D: Raffinose**:
- Raffinose is a trisaccharide made up of three monosaccharides: glucose, galactose, and fructose. It fits the criteria for oligosaccharides as it contains more than two monosaccharide units.

3. **Conclusion**:
Based on the analysis, the only option that does not qualify as an oligosaccharide is **Option A: Insulin**.

### Final Answer:
**Insulin is not an oligosaccharide.**

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