Select odd one out from the following list of compounds.
`CH_4, C_2H_4, C_2H_6, C_3h_8`

Explanation

To determine the odd one out from the list of compounds: CH₄, C₂H₄, C₂H₆, and C₃H₈, we need to classify each compound based on their chemical structure and properties.

### Step 1: Identify the compounds
- **CH₄**: This is methane, which is an alkane (saturated hydrocarbon).
- **C₂H₄**: This is ethylene, which is an alkene (unsaturated hydrocarbon).
- **C₂H₆**: This is ethane, which is an alkane (saturated hydrocarbon).
- **C₃H₈**: This is propane, which is an alkane (saturated hydrocarbon).

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