The correct answer is D.
A pure market economy, or capitalist economic system is characterized by zero goverment intervention in the economy. Instead, markets are allowed to freely fluctuate, and the interactions between the economic agents (households, firms and public sector) determine the prices and the output in both product and factor markets.
Therefore, if the US authorities intend to control banks and businesses, such action is violating the "zero interventionism" principle and the laissez-faire approach, hence the main criteria of capitalism.