Why was wudi one of china’s most significant rulers?

a. he expanded the empire and set up the civil service system that was used in china for many years after his rule.
b. he maintained economic stability but he mistreated the people whom grew dislike of him.
c. he was only supported peasants so he made reforms that solely benefited them.
d. he was a fair ruler but he did not trade often with foreign governments which caused a collapse in china’s economy.