The two functional groups characteristic of sugars are

Options

A. carbonyl and hydroxyl
B. carbonyl and phosphate
C. carbonyl and methyl
D. hydroxyl and methyl

Answer

To answer the question about the two functional groups characteristic of sugars, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Sugars**: Sugars are classified as soluble carbohydrates. They are organic compounds primarily composed of carbon (C), hydrogen (H), and oxygen (O).

2. **Identifying Functional Groups**: Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules.

3. **Common Functional Groups in Sugars**: The two main functional groups that are characteristic of sugars are:
- **Carbonyl Group (C=O)**: This group consists of a carbon atom double-bonded to an oxygen atom. In sugars, the carbonyl group can be found in two forms: as an aldehyde (at the end of the carbon chain) or as a ketone (within the carbon chain).
- **Hydroxyl Group (-OH)**: This group consists of an oxygen atom bonded to a hydrogen atom. Hydroxyl groups are present in all sugars and contribute to their solubility in water.

4. **Conclusion**: Therefore, the two functional groups characteristic of sugars are the **carbonyl group** and the **hydroxyl group**.

### Final Answer:
The two functional groups characteristic of sugars are the **carbonyl group** and the **hydroxyl group**.

---