Some tribes are nomadic because a)they had plenty of resources b)they had large amounts of food c)they wanted to escape hot weather or d)they build large houses made of hide

Your answer would be C, they wanted to escape hot weather.

A :They had plenty of resources: That would make no sense, because then there would be no reason for them to go to other places if they had everything they needed in that place.

B: They had large amounts of food: Same thing with A.

D: They build large houses out of hide: If they were nomadic, they wouldn't build large houses because they wouldn't bring them around.