Final answer:
To make a person's hand form a fist, Jose Delgado would need to stimulate the motor cortex, specifically the primary motor cortex in the precentral gyrus of the frontal lobe, which plays a key role in planning movement and triggering muscle contraction.
Step-by-step explanation:
To trigger a person's hand to make a fist, the correct answer is a. motor cortex. When discussing movements like making a fist, this area of the brain, particularly the primary motor cortex, is crucial.
The primary motor cortex is located in the precentral gyrus of the frontal lobe, and it is known to receive input from various brain regions to plan movement, ultimately sending signals through the spinal cord to stimulate skeletal muscle contraction.
Notably, neurosurgeon Walter Penfield contributed significantly to our understanding of the primary motor cortex through his work with electrical stimulation of the brain's surface during surgery.