What was the main reason the united states announced the open door policy? to spread democracy to southeast asia to prevent the victory of the chinese communists to ensure that u. s. businesses could operate in china to remove restrictions on chinese immigration to the united states

What is the main difference between primary and secondary sources? a. primary sources are historical documents, and secondary sources are modern-day documents. b. primary sources are derived from museums and archives, and secondary sources are created by history students and academics. c. primary sources are found in ancient places with a rich history, and secondary sources are found in historical journals and blogs. d. primary sources are created during a particular historical era, and secondary sources are created by studying primary sources.