In humans, there are .......... pairs of cranial nerves and .......... pairs of spinal nerves respectively.

The correct option is A 12, 31

• Thirty-one pairs of spinal nerves emerge from the spinal cord and extend through the protective, bony spinal column.
• The spinal nerves carry sensory nerve impulses towards the spinal cord and brain. They carry motor nerve impulses from the brain to the rest of the body.
• Twelve pairs of cranial nerves emerge from the brain.
• Most of these nerves supply the head, face, neck, shoulders chest and abdomen.
• The cranial nerves contain sensory and/or motor fibers, which control various conscious and unconscious functions.

Therefore, the correct answer is option A.