The Yuan dynasty relied on a large organization to govern.
The Yuan dynasty succeeded by continuing Sung civil service practices.
The Yuan dynasty benefited from appointing people of a variety backgrounds.
The Yuan dynasty was ruled mainly by bureaucrats as the khans had little real power.
This is because he relied on hiring people to govern these provinces. You can see he hired a lot of people to this, so there must be a large organization he relied upon to govern his nation. Therefore, it is A.
