Select odd one out from the following list of compounds.
`C_3H_4, C_2H_2, C_2H_6, C_4H_6`

Explanation

To determine the odd one out from the list of compounds \(C_3H_4\), \(C_2H_2\), \(C_2H_6\), and \(C_4H_6\), we will analyze each compound based on their molecular formulas and classify them as alkanes, alkenes, or alkynes.

### Step-by-Step Solution:

1. **Identify the General Formulas:**
- Alkanes: \(C_nH_{2n+2}\)
- Alkenes: \(C_nH_{2n}\)
- Alkynes: \(C_nH_{2n-2}\)
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