While Professor Travis is on the phone, he notices a glass vase sliding off the top shelf of his bookcase, about to fall on his dog. He moves quickly to catch the vase and prevent it from falling on his dog. In the context of the cerebral cortex, the quick movement of his hand is most likely caused by a process in the________.

a. somatosensory cortex.
b. motor cortex
c. Wernicke's area.
d. temporal lobe