Why were north and south america settled later than other continents? a. they were far away and across oceans b. their terrain was unattractive to humans c. their climate was unattractive to humans d. their plants and animals were unattractive to humans?

The answer here is A. Because North and South America is sandwiched between both the Atlantic and Pacific oceans, they weren't found until later. To make things worse, people, for the longest time, believed that the world was flat, and if you traveled too far, you would actually fall off the Earth. This, as you could imagine, discouraged many explorers from going too far. 

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