Which of the Following MOST Contributed to the Development of a Market

Which of the following MOST contributed to the development of a market economy in the United States?

A) internal transportation and communication projects that increased the flow of goods
B) a general trend toward farming for consumption alone
C) lines in the Constitution stipulating the role of the federal government in infrastructure
D) a decreasing standard of living overall due to more limited job opportunities
E) the decline of the lumber industry due to the growing scarcity of natural resources