In order to monitor and limit trade with the Europeans, the Ming Dynasty expected them to make this payment to Ming rulers.

Tribute System

Explanation:

Over time the Chinese government developed a mechanism known as the “tribute system” to deal with the outside world. Under this system a tribute state accepted its vassal status to the Chinese and was required to exchange envoys and gifts, monitor foreign trade, and handle diplomatic relations.

answer; i believe the correct answer is (the willamete valley);

answer is b.

  it is always the best policy to have good communication and good relations between individuals and, specially, between leaders of the countries. for this purpose, among others, there is a common place, the united nations, where the representants can present his and learn about the other country's policies.