Question

There are 12 pairs of cranial nerves out of which there are
A. 3 sensory, 5 motor, 4 mixed
B. 2 sensory, 8 motor, 2 mixed
C. 5 sensory, 3 motor, 4 mixed
D. 4 sensory, 4 motor, 4 mixed

Answer 1

Hint: In a human, twelve pairs of cranial nerves exist. They have numbers from I to XII. A cranial nerve with two roots, a dorsal and a ventral root, emerges from the brain. Generally, the cranial nerves are medullated (having a myelin sheath).

Complete answer:
The nerves formed by the brain are called cranial nerves. There are 3 kinds of nerve fibers that hold impulses or sensations or stimuli. They are fibers of the sensory, motor, and mixed nerves. Sensory or afferent nerve fibers bring impulses or stimuli to the central nervous system from receptors such as the skin, eye, ear, etc. (brain and spinal cord).
The motor or efferent nerve fibers bring impulses or stimuli to the effectors such as muscles and glands from the central nervous system. Some nerves contain sensory and motor fibers, which is why they are mixed. There are 12 pairs of cranial nerves named facial, vestibulocochlear, glossopharyngeal, vagus, accessory and hypoglossal nerve, olfactory, optic, oculomotor, trochlear, trigeminal, abducens.
Out of these sensory nerves are olfactory optic vestibulocochlear and motor nerves are oculomotor trochlear abducens accessory and hypoglossal nerves mixed nerves are Trigeminal facial and glossopharyngeal and vagus.
Thus from the above discussion, it is clear that there are 12 pairs of cranial nerves out of which there are 3 sensory nerves 5 motor nerves, and 4 mixed nerves so option A is the correct answer.

Note: The types of nerves in the peripheral nervous system are cranial and spinal nerves. The primary distinction between cranial and spinal nerves is that cranial nerves originate from the brain and are distributed in areas of the head, neck, and face, while spinal nerves originate from the spinal cord and are distributed in other parts of the body, such as the skin, skeletal muscles, and blood vessels.