This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
Lacrimation is affected due to damage to which of the following nerves? 
Select and explain. 
A. Nasociliary nerve, B. Greater petrosal nerve, C. Trigeminal nerve, D. Anterior ethmoid nerve
B: Greater petrosal nerve
Answer: B: Greater petrosal nerve 
Explanation: Answer- B (Greater petrosal nerve)The greater petrosal nerve is a branch of the facial nerve. It gives secretomotor fibers to the pterygopalatine ganglion along with lesser petrosal nerve. The postganglionic fibers innervate the lacrimal gland and are responsible for the formation of tears.Greater petrosal nerve damage will deprive the lacrimal gland of its secretomotor fibers and this would lead to the absence of tears.Greater petrosal nerve damage can happen in case of intrapetrosal mass lesions, a trauma in case of temporal bone injuries, etc.