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': 'Causes of abnormal uterine bleeding prior to menarche are all except \nSelect and explain. \nA. Vulvovaginitis, B. Foreign body and abuse, C. Anovulation, D. Precocious puberty', 'role': 'user'}, {'content': 'Answer: C \nExplanation: AUB resulting from anovulation is seen in adolescent age group, not prior to menarche.', 'role': 'assistant'}]