Which one of the following compounds does not decolourise bromine water?

Decolourization of bromine water occurs if the compound reacts with bromine.Cyclohexane: It is a saturated hydrocarbon (alkane). It does not react with bromine water in the dark or at room temperature. Thus, it does not decolourise it.Phenol: It is highly activated towards electrophilic substitution. It reacts with bromine water to form a white precipitate of $2,4,6\text{-tribromophenol}$, decolourising the water.Styrene: It contains an alkene double bond in the side chain which undergoes addition reaction with bromine, decolourising it.Aniline: Similar to phenol, it is highly activated and forms $2,4,6\text{-tribromoaniline}$, decolourising bromine water.