I think it is D hope this helps
Christopher Columbus discovered the Caribbean islands while Ferdinand Magellan was the first to circumnavigate the earth.
Explanation:
Christopher Columbus was the earlier one of the two great explorers and his exploration was to the west of Spain where he eventually discovered the Caribbean islands and led o the discovery of the Americas.
Ferdinand Magellan was also a very ambitious sailor and he tried to circumnavigate the earth with his expedition of six ships.
HE did this around 1520 and was eventually successful and in the process had discovered the Magellan straights too.
I think the answer would be A which would be that it required all citizens to support the slave system.
