The functional group present in aldehydes is -

Options

A. `-OH`
B. `-CHO`
C. `-COOH`
D. `-COOR`

Explanation

To determine the functional group present in aldehydes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Functional Groups**:
- A functional group is a specific group of atoms within a molecule that is responsible for the characteristic chemical reactions of that molecule.

2. **Identifying Aldehydes**:
- Aldehydes are a class of organic compounds that contain a carbonyl group (C=O) with at least one hydrogen atom attached to the carbon atom of the carbonyl group.

3. **Recognizing the Carbonyl Group**:
- The carbonyl group in aldehydes is represented as -CHO. This indicates that the carbon atom is double-bonded to an oxygen atom and single-bonded to a hydrogen atom.

4. **Evaluating Given Options**:
- If we have options like:
- A) OH (which is for alcohols)
- B) CHO (which is for aldehydes)
- C) COOH (which is for carboxylic acids)
- D) COOR (which is for esters)
- We can see that the option that corresponds to the functional group of aldehydes is CHO.

5. **Conclusion**:
- Therefore, the functional group present in aldehydes is -CHO.

### Final Answer:
The functional group present in aldehydes is -CHO.

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