Select the principal group when the following groups are present in a molecule.
`-OH , gt C=O ,-COOH`

Explanation

To determine the principal group among the functional groups -OH (hydroxyl), C=O (carbonyl), and -COOH (carboxylic acid), we follow these steps:

### Step-by-Step Solution:

1. **Identify the Functional Groups**:
- The groups present in the molecule are:
- Hydroxyl group (-OH)
- Carbonyl group (C=O)
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