Final answer:
Option (b), The abducens nerve (cranial nerve VI) is classified as a motor nerve, responsible for the lateral movement of the eyeball.
Step-by-step explanation:
The abducens nerve (cranial nerve VI) is classified as a motor nerve. This nerve is responsible for the contraction of the lateral rectus muscle, one of the extraocular muscles that control eye movements. Specifically, the abducens nerve enables the lateral movement of the eyeball (abduction), allowing for horizontal motion.
In terms of cranial nerve functions, according to a common mnemonic 'Some Say Marry Money But My Brother Says Brains Beauty Matter More', which correlates to the respective functions of the cranial nerves, the abducens nerve is a motor nerve.