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: Medicine
Sea saw nystagmus is seen in - 
Select and explain. 
A. Anterior longitudinal fasiculus, B. Craniopharyngioma, C. Medullary lesion, D. GB. Syndrome
B: Craniopharyngioma
Answer: B: Craniopharyngioma 
Explanation: None