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': 'Which of the following ovarian tumour is most prone to undergo torsion during pregnancy? \nSelect and explain. \nA. Serous cystadenoma, B. Mucinous cystadenoma, C. Dermoid cyst, D. Theca lutein cyst', 'role': 'user'}, {'content': 'Answer: C \nExplanation: “Incidence of dermoid cyst increases two times in pregnancy and it becomes the most commonly diagnosed ovarian tumour during pregnancy.”\nDutta Obs. 7/e, p 310\n“A benign cystic teratoma is the most common neoplasm to undergo torsion.”\nNovak 14/e, p 510', 'role': 'assistant'}]