A 23-year-old girl comes for evaluation in psychiatry outpatient. The patient repos that she has been facing increasing anxiety since she got promoted. Earlier her office was on 1st floor and now she had to shift to 10th floor. She repoed that she has always been uncomfoable of heights and had avoided many jobs in past as they were in high rise buildings. She also lives at ground floor. Since, she got promoted, she has been using alprazolam to keep herself calm, but she wants a proper solution to her problem. Which is the most appropriate treatment for her condition?