In 1636, the Tokugawa shogunate began an isolationist policy which banned Japanese people from leaving the country and forbade most foreign countries from trading with Japan. The Japanese had very little contact with foreigners until the arrival of Commodore Matthew Perry in 1853. Which of the following factors helped Japan maintain its period of isolation?
A. Japan had the world's strongest army and navy and defeated all attempts at foreign invasion.
B. Japan did not have any resources that other countries wanted.
C. Since Japan is made up of a series of islands, it was geographically isolated from other regions.
D. Because of widespread disease in Japan, few foreigners wanted to travel there.
