Correct Option: C

When water combines chemically with other elements, the process is called hydration. In organic chemistry, a hydration reaction is a chemical reaction in which a hydroxyl group (–OH) and a hydrogen cation (an acidic proton) are added to the two carbon atoms bonded together in the carbon-carbon double bond which makes up an alkene functional group. The reaction usually runs in a strong acidic, aqueous solution. Hydration leaves the non-water component intact.