The correct option is Alkanes.
Explanation
Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon. They are primarily classified based on the type of covalent bonds existing between carbon atoms. This classification distinguishes between saturated hydrocarbons (single bonds) and unsaturated hydrocarbons (multiple bonds).
Option Analysis
- Alkanes (Correct): Alkanes are saturated hydrocarbons in which all carbon atoms are bonded to each other via single covalent bonds. They follow the general formula $C_nH_{2n+2}$. Due to the absence of pi bonds, they are relatively less reactive compared to unsaturated hydrocarbons. Examples include Methane ($CH_4$) and Ethane ($C_2H_6$).
- Alkenes (Incorrect): Alkenes are unsaturated hydrocarbons that contain at least one carbon-carbon double bond. They follow the general formula $C_nH_{2n}$. The presence of the double bond makes them more reactive than alkanes.
- Alkynes (Incorrect): Alkynes are unsaturated hydrocarbons characterized by the presence of at least one carbon-carbon triple bond. They follow the general formula $C_nH_{2n-2}$.
- Alcohols (Incorrect): Alcohols are organic compounds containing a hydroxyl functional group (-OH) attached to a carbon atom. While they are derived from hydrocarbons, they are not classified as hydrocarbons themselves; they are hydrocarbon derivatives.
Key Takeaway: Hydrocarbons with only single bonds are called Alkanes (saturated). Those with double bonds are Alkenes, and those with triple bonds are Alkynes (both unsaturated).