TOEFL Listening: TPO-TOEFL听力TPO - Z0N1NH2D5IEB8P18R$

Why does the professor mention moveable floorboards on the stage in Wheatley's production? A. To explain the reason for an unexpected technical problem B. To highlight one of the production's innovative features C. To point out a similarity between early and modern theater in the United States D. To give an example of a modification that was made for the ballet troupe