Alex and His Family Moved into an Apartment on the 98

Multiple Choice

Alex and his family moved into an apartment on the 98?? floor of a building.The first few times that Alex used the elevator,his ears popped and Alex found the sensation uncomfortable.As a result,whenever Alex enters a building with an elevator,he feels his ears pop before he gets to the elevator.In the context of classical conditioning,which of the following is the conditioned response?

A) Alex's ears popping in the elevator
B) Alex entering his building elevator the first time
C) Alex entering any building with an elevator
D) Alex's ears popping when he enters a building with an elevator