<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 38-year-old man comes to the physician because of persistent sadness and difficulty concentrating for the past 6 weeks. During this period, he has also had difficulty sleeping. He adds that he has been feeling down most of the time since his girlfriend broke up with him 4 years ago. Since then, he has only had a few periods of time when he did not feel that way, but none of these lasted for more than a month. He reports having no problems with appetite, weight, or energy. He does not use illicit drugs or alcohol. Mental status examination shows a depressed mood and constricted affect. Which of the following is the most likely diagnosis?? A: Major depressive disorder, B: Bipolar affective disorder, C: Cyclothymic disorder, D: Persistent depressive disorder, E: Adjustment disorder with depressed mood,  <response>: This is a clinical vignette describing a 38-year-old man with persistent sadness, difficulty concentrating, and sleep disturbances over the past 6 weeks. He also has a history of feeling down most of the time since a breakup 4 years ago, with only brief periods of feeling better. He has no changes in appetite, weight, energy, or substance use. Mental status exam shows depressed mood and constricted affect. The key features here are the persistent depressed mood for most days over the past 6 weeks, along with associated symptoms like concentration issues and sleep disturbances. His longer history of depressed mood over the past 4 years, with only brief periods of improvement, is also notable. This history and presentation is most consistent with persistent depressive disorder dysthymia, which involves chronic, persistent depressive symptoms lasting 2 or more years.The lack of manichypomanic episodes makes bipolar disorder unlikely. Major depressive disorder episodes typically last weeks to months, not years. Cyclothymic disorder involves fluctuating mood symptoms, not persistent depression. Adjustment disorder requires symptoms onset within 3 months of a stressor, not years later.D: Persistent depressive disorder 