Answer:
B. Isolation caused the Chinese people to lag behind the world in technological and cultural advancements.
China considered isolationism whenever they felt their culture was being threatened. They didn't want the Chinese people to forget or change their culture so the country isolated itself from the rest of the world. However, the side effects were that China did fall behind in the latest technology and cultural advancements as well as being behind in trade. China was no longer considered one of the most powerful countries in the world when it came to trading. They fell behind and it caused many Dynasties to fall.
(Such as the Ming Dynasty)
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