Answer:
b) convolutions
Step-by-step explanation:
The part that makes the outer rim of the cerebrum is the cerebral cortex. It is composed of gray matter. The billions of neurons of the cerebral cortex are organized in distinct layers. During embryonic development, enlargement of the brain is accompanied by even more enlargement in the gray matter of the cerebral cortex. However, it fits into the skull due to its folds which are also called convolutions or gyri. The cortical region rolls and folds on itself.