Question

Which of the following has the smallest brain capacity?

Answer 1

Brain capacity or cranial capacity is the volume of the interior of the cranium of vertebrates that possess a cranium (skull cover) and a brain (organ). Brain capacity is a metric that is used to approximate the size of the brain, which is also suggestive of the intelligence of the organism.

The cranial capacity of the above given organisms are as follow:
Homo sapiens - 1450cc
Homo habilis - 650cc to 800cc
Homo neanderthalensis - 1400cc
Homo erectus - 900cc

Thus, out of the given organisms, Homo habilis with 650-800cc has the smallest brain capacity.