To solve this problem, we need to identify the type of halide in the given compound.$\newline$The structure provided is:$\newline$• A benzene ring with a side chain: CH=CH-CH-CH$_2$-CH$_3$ with a halogen (X) attached to the third carbon.$\newline$Let's analyze the options:$\newline$1. Benzylic halide: A halogen attached to a carbon adjacent to a benzene ring.$\newline$2. Aryl halide: A halogen directly attached to a benzene ring.$\newline$3. Allylic halide: A halogen attached to a carbon adjacent to a carbon-carbon double bond.$\newline$4. Vinylic halide: A halogen attached to a carbon that is part of a carbon-carbon double bond.$\newline$In the given compound, the halogen (X) is attached to a carbon that is adjacent to a carbon-carbon double bond.$\newline$This fits the definition of an allylic halide.$\newline$Therefore, the correct option is Option 3: Allylic halide.