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
Which of the following has LEAST chance of progression in multiple sclerosis? 
Select and explain. 
A. Optic nerve involvement, B. Absence of oligoclonal band in CSF, C. Transverse myelitis, D. Pyramidal tract involvement
B: Absence of oligoclonal band in CSF
Answer: B: Absence of oligoclonal band in CSF 
Explanation: None