Bell’s palsy is an acute, usually temporary condition resulting from damage or trauma of:

Correct option is D

Ans. (d) Sol. Bell’s palsy is caused by damage to the facial nerve, which is cranial nerve VII. This nerve controls the muscles of facial expression, and damage to it results in temporary facial paralysis or weakness on one side of the face.
Explanation of each option:
· (a) Cranial III – Incorrect. Cranial nerve III is the oculomotor nerve, which controls eye movements and pupil constriction, not facial expression.
· (b) Cranial IV – Incorrect. Cranial nerve IV is the trochlear nerve, which controls the superior oblique muscle of the eye.
· (c) Cranial V – Incorrect. Cranial nerve V is the trigeminal nerve, responsible for sensation in the face and motor functions such as chewing, but it does not control facial expressions.
· (d) Cranial VII – Correct. Cranial nerve VII is the facial nerve, and Bell’s palsy results from its dysfunction, causing weakness or paralysis of the facial muscles.