B.) to leave alone and let be
Laissez-faire refers to a free market economic policy where the government has no control over the economy. It is a French term which means to "let it be".
Capitalism in its pure form is a laissez-faire economic system. During the late 19th century, the US practiced laissez-faire capitalism. The government had no regulations on the economic system and employers were allowed to run their businesses as they wished. In a free system like this there are opportunities to become very wealthy but workers are often exploited.
The different cultures were established in Asia and carried into the Americas. B. Constant warfare among the different Native American groups led to cultural differences.
D) improved the standard of living for many families.