Which shows the general structure of a carboxylic acid?
O A. R
O-R
R
O R
B. R-O-R
C. R-OH
OD ROH

Explanation:
A carboxylic acid is an organic acid that contains a carboxyl group (C(=O)OH) attached to an R-group. The general formula of a carboxylic acid is R−COOH or R−CO2H, with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely.