Substitution reaction is a characteristic of

Options

A. alkene
B. carbon monoxide
C. alkyne
D. paraffin

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Substitution Reactions**: A substitution reaction is a type of chemical reaction where one atom or group of atoms in a molecule is replaced by another atom or group of atoms. This is a key characteristic of certain types of hydrocarbons.

2. **Identifying Hydrocarbon Types**:
- **Alkenes**: These are hydrocarbons that contain at least one carbon-carbon double bond (C=C).
- **Alkynes**: These contain at least one carbon-carbon triple bond (C≡C).
- **Alkanes (Paraffins)**: These are saturated hydrocarbons with only single bonds (C-C).
- **Carbon Monoxide (CO)**: This is a simple molecule consisting of one carbon and one oxygen atom, and it does not participate in substitution reactions.

3. **Analyzing the Options**:
- **Option A (Alkene)**: Alkenes typically undergo addition reactions rather than substitution reactions due to the presence of double bonds.
- **Option B (Carbon Monoxide)**: This is not a hydrocarbon and does not undergo substitution reactions.
- **Option C (Alkyne)**: Alkynes also primarily undergo addition reactions due to their triple bonds.
- **Option D (Paraffin/Alkane)**: Alkanes are known for undergoing substitution reactions, particularly when reacting with halogens in the presence of UV light.

4. **Example of Substitution Reaction**:
- Consider ethane (CH3CH3). When ethane reacts with chlorine (Cl2) in the presence of UV light, one hydrogen atom is replaced by a chlorine atom, resulting in chloroethane (CH3CH2Cl) and hydrochloric acid (HCl). This exemplifies a substitution reaction.

5. **Conclusion**: Based on the analysis of the options and the characteristics of the hydrocarbons, the correct answer is **Option D (Paraffin/Alkane)**, as substitution reactions are characteristic of alkanes.