Concept:
Many organic compounds have specific industrial uses.
Step 1: Check correct pairs.
- Esters of benzoic acid are used in perfumery.
- Ethanoic acid is used in food industry (vinegar, preservatives).
- Methanoic acid is used in electroplating.
- Sodium benzoate is a food preservative.
Step 2: Check incorrect pair.
Hexanedioic acid (adipic acid) is mainly used in manufacture of nylon-6,6, not detergents.
Step 3: Final answer.
\[
\boxed{\text{Hexanedioic acid -- Detergents}}
\]
Hence, correct option is (B).