The answer is D. .Hoover suggested that people tell more jokes
The policy is known as the "Open Door Policy."
John Hay created this idea in hopes that America and countries all over Europe could trade peacefully with China. This concept was developed in order to protect America's trade interests while also ensuring that no other country would establish a monopoly on trade with China. Within this policy, all countries would agree not to interfere with another country's trade with China.
If I understand your question correctly, I believe it was the Ming Dynasty which lasted from 1338-1644.
