Which of the following is an example of ketohexose?

Options

A. mannose
B. galactose
C. maltose
D. Fructose

Explanation

To determine which of the following is an example of a ketohexose, we need to understand the definitions of "keto" and "hexose."

### Step-by-Step Solution:

1. **Understanding Keto and Hexose**:
- **Keto**: Refers to the presence of a ketone group (C=O) in the molecule.
- **Hexose**: Refers to a sugar molecule that contains six carbon atoms.

2. **Identifying the Structure**:
- A ketohexose must have a ketone group and a total of six carbon atoms in its structure.

3. **Analyzing the Options**:
- We need to look at the given options (which are not provided in the question but typically include sugars like glucose, fructose, galactose, etc.) and identify which one has a ketone group and six carbons.

4. **Recognizing Fructose**:
- Fructose is a well-known example of a ketohexose. Its structure can be represented as:
- CH2OH - C(=O) - CH(OH) - CH(OH) - CH2OH
- In this structure, the ketone group (C=O) is located at the second carbon atom, and there are a total of six carbon atoms.

5. **Conclusion**:
- Therefore, the correct answer to the question is **fructose**, as it is the only option that qualifies as a ketohexose.

### Final Answer:
The example of a ketohexose is **fructose**.

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