The information used by the computer to make its detailed maps ______.
Ⅰ. was gathered by the Defense Department and the U. S. Geological Survey
Ⅱ. shows points roughly 200 feet apart
Ⅲ. involves altitude measurements

A．the reasons for the Progressive Movement
B．the problems that American society faced between the 1890s and the end of World War I
C．the causes and contents of the Progressive reform
D．the belief that Americans possessed in their society

A．there was little equal opportunity for general Americans
B．industry developed very rapidly
C．thousands of people immigrated to the United States
D．economic depression did great harm to its development