When identifying functional groups in organic chemistry, which of the following represents a common functional group and its characteristic?
a. Hydroxyl group (–OH): A functional group commonly found in alcohols, characterized by an oxygen-hydrogen bond.
b. Carboxyl group (–COOH): A functional group found in ketones, characterized by a carbonyl group bonded to an alcohol group.
c. Ester group (–COO–): A functional group found in esters, characterized by a carbonyl group bonded to an oxygen atom with an alkyl or aryl group.