This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Facial Nerve And Its Disorders, Subject name: ENT
Dryness of eye is caused by injury to facial nerve at: 
Select and explain. 
A. Chorda tympani, B. Vertical segment, C. Tympanic segment, D. Geniculate ganglion
D: Geniculate ganglion
Answer: D: Geniculate ganglion 
Explanation: (d) Geniculate ganglion(Ref. Cummings, 6th ed., 2606)Whenever there is injury before or at the origin of the greater superficial petrosal nerve (i.e. before or at the Geniculate ganglion) which is responsible for lacrimation there will be dry eye on the same side.Tympanic segment, Vertical segment and Chorda tympani all are beyond the geniculate ganglion.