This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endometriosis & H, Subject name: Gynaecology & Obstetrics
[{'content': 'A 20 year old woman gives a history of pain in the lower abdomen for 2-3 days every month staing approximately 3 days before the menses. The most probable etiology is? \nSelect and explain. \nA. Mittelschmerz, B. Fibroid, C. Endometriosis, D. Pelvic tuberculosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Menstrual pain is known as dysmenorrhea & if it stas 2 - 3 days before the onset of menstruation that is known as congestive dysmenorrhea. Endometriosis most characteristically presents with congestive dysmenorrhea. Fibroid classically presents with spasmodic dysmenorrhea (congestive dysmenorrhea can also seen) which is present mostly on the first & second day of the menstruation. Mittelschmerz (ovulation pain) - ovulation pain occurs in mid cycle.', 'role': 'assistant'}]