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': "OCP's are contraindicated in all except : \nSelect and explain. \nA. Intermittent vaginal bleeding, B. Uterine fibroids, C. H/0 thromboembolism, D. Cardiac abnormalities", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Uterine fibroids', 'role': 'assistant'}]