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: Ophthalmology
The MOST likely site of lesion in a patient with Wernicke's hemianopic pupil is: 
Select and explain. 
A. Optic nerve, B. Optic tract, C. Optic chiasma, D. Optic radiation
B: Optic tract
Answer: B: Optic tract 
Explanation: Wernicke's hemianopic pupil indicates lesion in the optic tract. In this condition light reflex is absent when light is thrown on temporal half of the retina of the affected side and nasal half of retina of the opposite side. In this condition light reflex is present when light is thrown on nasal half of affected side and temporal half of affected side. This patient also has homonymous hemianopia. Ref: Textbook of Ophthalmology edited by Sunita Agarwal, page 304.