This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
[{'content': 'Cycle which is absent in humans is \nSelect and explain. \nA. Menstrual cycle, B. Ovarian cycle, C. Hormonal cycle, D. Estrous cycle', 'role': 'user'}, {'content': 'Answer: D \nExplanation: .', 'role': 'assistant'}]