What was one major achievement of Emperor Wudi?

A. He founded the Han dynasty.
B. He expanded China to the north and south.
C. He united China under a Legalist government.
D. He built the Great Wall of China.

b

Explanation:

emperor wudi was interested in expanding the chinese empire

i think the answer is the one about environmental and social health.

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the causes of the dust bowls were severe droughts,   lands became dry and hard, temperature was higher than usual, hot and dry conditions killed crops, high winds. because of those factors, the winds kicked up dry soil and created clouds of dust.