Answer:
Korea: Developed on a peninsula
Chinese: Developed on river valleys
Japanese: Developed on a an archipelago.
Explanation:
Korean civilization developed on the Korean Peninsula and now consists of two different states North and South Korea. North Korea is autocratic communist country, while South Korea is a democratic country.
Chinese civilization is one of the oldest civilizations in the world it developed in the East Asia in the river valley of the Yellow River. Now it is the most populous country in the world with about 1.404 billion people. It is a communist country lead by the Communist Party of China.
Japan has developed on the Japase archipelago consisting of about 6.852 islands, with five main islands being Honshu, Hokaido, Kyushu, Shikkoku and Okinawa. Japan is now a constitutional monarchy.
This plan was called the "Open Door Policy". This policy was proposed by the USA in 1899. Under this, all western nations would have equal opportunities to trade in China. Thiss was in support of Chinese territorial and administrative integrity. It lasted for 40 years and it became the foundation for the American foreign policy in East Asia at that time.
