Pretty sure it is C because it it divisible by 3. If you divide 15 you get 5 and if you divide 6 you get 2.
Answer:
Mansa Musa inherited a kingdom that was already wealthy, but his work in expanding trade made Mali the wealthiest kingdom in Africa. His riches came from mining significant salt and gold deposits in the Mali kingdom. Elephant ivory was another major source of wealth.
Explanation:
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