This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mood disorders, Subject name: Psychiatry
[{'content': 'To diagnose depression, symptoms should last at least for \nSelect and explain. \nA. 4 weeks, B. 6 months, C. 2 weeks, D. 6 weeks', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Symptoms should last for at least 2 weeks, for cyclothymia -mild form of depression, symptoms should last for 2 years Ref: Essentials of postgraduate psychiatry By JN Vyas 1st ed Pg 604-607', 'role': 'assistant'}]