[单项选择]Reading 3 "’Building with Arches"
Round Arch and Vault
→ Although the round arch was used by the ancient peoples of Mesopotamia several centuries before our common era, it was most fully developed by the Romans, who perfected the form in the 2nd century B.C.E. The arch has many virtues. In addition to being an attractive form, it enables the architect to open up fairly large spaces in a wall without risking the building’s structural soundness. These spaces admit light, reduce the weight of the walls, and decrease the amount of material needed. As utilized by the Romans, the arch is a perfect semicircle, although it may seem elongated if it rests on columns. It is constructed from wedge-shaped pieces of stone that meet at an angle always perpendicular to the curve of the arch. Because of tensions and compressions inherent in the form, the arch is stable only when it is complete, when the topmost stone, the keystone, h
A. It was a characteristic of construction with pointed arches.
B. It was too difficult to make windows in the heavy materials.
C. Openings for light could have compromised the structure.
D. Reinforcements covered the areas where light could shine in.