<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 23-year-old woman is brought to the physician by her father because of irritability, mood swings, and difficulty sleeping over the past 10 days. A few days ago, she quit her job and spent all of her savings on supplies for a genius business plan. She has been energetic despite sleeping only 12 hours each night. She was diagnosed with major depressive disorder 2 years ago. Mental status examination shows pressured speech, a labile affect, and flight of ideas. Throughout the examination, she repeatedly states I feel great, I dont need to be here. Urine toxicology screening is negative. Which of the following is the most likely diagnosis?? A: Delusional disorder, B: Bipolar disorder type II, C: Bipolar disorder type I, D: Schizoaffective disorder, E: Attention-deficit hyperactivity disorder,  <response>: This is a clinical vignette describing a 23-year-old woman with recent onset irritability, mood swings, decreased need for sleep, increased activity, impulsive behavior, and grandiose thoughts, along with a prior history of major depressive disorder. The key features here are the acute change in mood, behavior, and energy level, along with mood lability, pressured speech, flight of ideas, and grandiosity, in the setting of a prior depressive episode. This presentation is most consistent with mania, indicating a diagnosis of bipolar disorder. The lack of psychotic symptoms makes schizoaffective disorder unlikely. The chronicity makes ADHD unlikely. The presence of a prior depressive episode makes bipolar I more likely than bipolar II. Therefore, the most likely diagnosis is bipolar disorder type I.C: Bipolar disorder type I 