Secretary of state john hay promoted in which all nations agreed to let the others trade with china.

question 3 options:

the open door policy

the european trade alliance

the treaty of japan

the platt amendment

The correct answer is the Open Door Policy.

Explanation:

Open Door Policy was a United States policy concerning foreign affairs that was established to allow that all countries could have trade with China. The policy also established that any country could have trading rights that were unique in a certain area.

The policy was promoted by John Hay during the 19th century. Another important aspect was that Chinese authorities could not get tariffs and at the same time, any country could allow a treaty port in which the Chinese had the opportunity to do this. The policy was created because Chinese markets attracted the United States and this country wanted to trade with them.  

an era of negotiation.

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