This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anatomy of Middle Ear, Subject name: ENT
[{'content': 'Stapes foot plate covers: \nSelect and explain. \nA. Round window, B. Oval window, C. Sinus tympani, D. Pyramid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The Oval window is covered by the footplate of stapes. The Round window is covered by secondary tympanic membrane.', 'role': 'assistant'}]