Since the end of World War II, manufacturing firms in the United States and in Europe have been moving farther and farther outside of central cities. At the same time, firms in finance, insurance, and other parts of the service sector have been locating near downtown areas in tall buildings.

What kinds of buildings represent substitution of capital for land?

A. Skyscrapers.

B. Government buildings.

C. Shipping facilities.

D. Factories.