Which of the following is an allylic halide?
Allylic halides have the halogen atom attached to an sp3-hybridized carbon adjacent to a carbon-carbon double bond. This follows from NCERT principle where the relation explains the outcome clearly for students in simple steps.
Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.