If a country only trades internally on domestic markets, then the prices, supply, and demand for goods are all set within that local economy native to the country's own markets. However, if a country such as the United States engages in global trade, then it becomes exposed to the whole world's supply, demand, and resulting price structures. As such, the answer is D. International trade makes Americans more connected to work markets, because they are required to work within the forces and structures of those markets to do business.