Which statement about the open door notes is true?

a. they were written by the japanese ambassadors?

b. they were sent to european powers?

c. they were written by representatives of the european powers?

d. they were sent to the qing dynasty?

Open door notes were sent to the European powers.

Explanation:

Japan and other European powers had a great influence on china in all spheres and they dominated in Chinese economy. United states could not achieve its influence as it was late in establishing its superiority and imperialism and hence John  Hay advocated open door policy which removed all imperialistic dominance over china and it enhanced trading rights to all nations in china.

In a way, this open door policy also safeguarded the interests of china and their trade relations with other countries. It promoted the equality of all countries in foreign trade with China.