A will be:

The answer is option 2.

The reaction will be :

Mechanism

Step 1:  The alkene is protonated and it gives rise to the more stable carbocation as shown below:

From the illustration shown above, we can see that there are two types of carbocations that can be formed from the protonation of the alkene, one is a primary carbocation and the other is a secondary carbocation. However, the secondary carbocation is far more stable and therefore, its formation is preferred over the formation of a primary carbocation.

Step 2: The halide ion nucleophile now attacks the carbocation. This reaction yields the alkyl halide. Since the formation of the secondary carbocation is preferred, the major product of this reaction would be 2-bromohexane  as illustrated below.