How did Mansa Musa become ruler of Mali? A. His father was king before him.
B. His boss, the previous king was lost at sea.
C. He killed the previous king.

I think it's a

Explanation:

well if he killed his father wouldn't the kingdom execute him

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.