The correct decreasing order of priority for the functional groups of organic compounds in the IUPAC system of nomenclature is:

The priority order for common functional groups in IUPAC nomenclature is:$-\text{COOH}>-{\text{SO}}_3\text{H}>-\text{COOR}>-\text{COCl}>-{\text{CONH}}_2>-\text{CN}>-\text{CHO}>-\text{CO}->-\text{OH}>-{\text{NH}}_2$.Based on the options, $-\text{COOH}>-{\text{SO}}_3\text{H}>-{\text{CONH}}_2>-\text{CHO}$ is correct.(Note: Some sources place sulphonic acid higher than carboxylic, but the standard AIEEE key usually follows Option B: $-{\text{SO}}_3\text{H}>-\text{COOH}\dots$)