The order of reactivity of alkyl halides towards elimination reaction is

3º > 2º > 1º

The correct order of reactivity of alkyl halides towards elimination reaction is (3) 3º > 2º > 1º.

The order of reactivity of alkyl halides towards elimination reaction is in the order of decreasing stability of the carbocation intermediate. The more stable the carbocation intermediate, the faster the elimination reaction.

Primary alkyl halides form the least stable carbocation intermediate, while tertiary alkyl halides form the most stable carbocation intermediate. Therefore, tertiary alkyl halides are the most reactive towards elimination reaction, followed by secondary alkyl halides and then primary alkyl halides.

Here is a table showing the order of reactivity of alkyl halides towards elimination reaction: