A trisaccharide is

Options

A. Galactose
B. Maltose
C. Raffinose
D. Mannose.

Answer

**Step-by-Step Solution:**

1. **Understanding the Definition of Trisaccharide**: A trisaccharide is a type of carbohydrate that is composed of three monosaccharide units. Monosaccharides are the simplest form of carbohydrates, and examples include glucose, galactose, and fructose.

2. **Identifying Common Trisaccharides**: To answer the question, we need to identify which of the given options is a trisaccharide. Common examples of trisaccharides include raffinose, maltotriose, and others.

3. **Evaluating the Options**:
- **Galactose**: This is a monosaccharide, not a trisaccharide.
- **Maltose**: This is a disaccharide, consisting of two glucose units.
- **Mannose**: This is also a monosaccharide, not a trisaccharide.
- **Raffinose**: This is a trisaccharide composed of three different monosaccharides: glucose, galactose, and fructose.

4. **Conclusion**: Based on the evaluation, the only option that qualifies as a trisaccharide is raffinose.

5. **Additional Information**: Raffinose is commonly found in various plants, such as beans, cabbage, and sprouts, which can help in identifying its presence in food sources.

**Final Answer**: The correct answer is raffinose, which is a trisaccharide.

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