Answer: A, C
4-Bromo-2-chlorophenol has prefixes in alphabetical order (bromo before chloro) with lowest locants; 3-methylbenzoic acid uses the acid as the parent. 2-Chloro-4-bromophenol breaks alphabetical order, and 3-carboxytoluene uses the wrong parent because carboxylic acid outranks the methyl-bearing hydrocarbon.