This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of Ovulation - Anovulation , Subject name: Gynaecology & Obstetrics
[{'content': 'Most common cause of DUB is? \nSelect and explain. \nA. Anovulatory, B. Ovulatory, C. Coagulapathy, D. Pregnancy related', 'role': 'user'}, {'content': 'Answer: A \nExplanation: ANSWER: (A) AnovulatoryREF: Novaks Gynaecology 14th ed page 461DUB is the term used to describe abnormal uterine bleeding for which no specific cause has been found.It most often implies a mechanism of anovulation. Most anovulatory bleeding is a result of estrogen breakthrough.It is a diagnosis of exclusion.', 'role': 'assistant'}]