Which of the following is a main roof type?

• A. Dome
• B. Gable
• C. Flat
• D. Arched

Answer: (C)

Roof types are categorized by the overall shape of the roof surface. A flat roof is the main roof type because it represents a broad, nearly horizontal roof plane that defines many modern and commercial buildings. It stands out as a primary classification, distinct from curved forms like domes or arches, which are specialized designs, and from pitched forms like gable roofs, which fall under a different category of roof shapes. In many building classifications and exam contexts, flat is treated as the fundamental or default roof type among the options, making it the best choice here.