This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
[{'content': 'Spasmodic dysmenorrhoea is seen in : \nSelect and explain. \nA. Endometriosis, B. DUB, C. Submucous fibroid, D. Ovarian cyst', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Submucous fibroid', 'role': 'assistant'}]