Which statement about the Tokugawa shogunate is accurate? A. It was a dynasty established after the shogun defeated Kublai Khan, and it limited foreign trade in order to protect Japanese business interests. B. It was established when leyasu defeated rival warlords; later rulers closed Japan to foreign trade to protect Japanese culture from western influence. C. Ieyasu started the dynasty when he defeated his rivals, brought Japan together under more democratic rule, and united the Japanese people by restricting foreign trade. D. Ieyasu decreed this series of laws to limit trade with foreigners in order to boost local economies and create unity among his people.