TOEFL Listening: TPO-TOEFL听力TPO - D71NU8I3B17U54A9R$

Why does the professor mention a piano recital? A. To illustrate that different kinds of performances require rooms with different reverberation times B. To demonstrate that the size of the instrument can affect its acoustic properties C. To cite a type of performance suitable for rectangular concert hall D. To exemplify that the reverberation time of a room is related to its size