The correct decreasing order of priority for the functional groups of organic compounds in the IUPAC system of nomenclature is
A. `-CONH_(2), -CHO, -SO_(3)H, -COOH`
B. `-COOH, -SO_(3)H, -CONH_(2), -CHO`
C. `-SO_(3)H, -COOH, -CONH_(2), -CHO`
D. `CHO, -COOH, -SO_(3)H, -CONH_(2)`
