Homo erectus was able to migrate out of africa because:
a. he developed extra body hair to survive in cold areas (like northern europe)
b. he doubled the amount of body fat which provided insulation in cold areas
c. by eating meat, he could migrate wherever animals are found, and live in cold areas where plant-eaters (like australopithecus) could not have found food during ice ages
d. all of the above

C)  by eating meat, he could migrate wherever animals are found, and live in cold areas where plant-eaters (like Australopithecus) could not have found food during Ice Ages

Explanation:

 Home erectus are the oldest humans species in the africa and they expand there range in the several continents like south east asia for the search of diet that includes meat and increasing the food supply in the environment seasonally and also live in cold area where plant eaters do not find enough food during ice ages. As, homo erectus are the posses the cultural and physical attributes.

b. lithosphere, asthenosphere, mesosphere   is the answer most likely