Final answer:
The minimal requirements for a theatre building are curtains, seats, and lobby.
Step-by-step explanation:
The minimal requirements for a theatre building are A) Curtains, seats, and lobby. The curtains provide a backdrop for the stage and allow for scene changes. The seats provide a place for the audience to comfortably watch the performance. The lobby serves as an entrance area and may include a ticket office, restrooms, and other amenities.