Look at the possible hydrogens that you can attack with a base. You have to attack a hydrogen adjacent to the carbon with the leaving group. If you attack that hydrogen, the only double bond it can form to make the leaving group leave is methylenecyclohexane. Hope that helps
In this case, you don't have to worry about that. The Br is directly attached to the CH2. The only possible H that can be attacked is the one that is at the C1 position on the cylcohexane. The electrons would form a double bond with the CH2 to "knock" off the Br. No other possible H can be attacked to make Br leave.
