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
Following are findings of GBS except 
Select and explain. 
A. Albumino-cytological dissociation, B. Helicobacter pylori is frequent cause, C. Perivenous lymphatic infiltrates, D. Febrile polyneuritis
B: Helicobacter pylori is frequent cause
Answer: B: Helicobacter pylori is frequent cause 
Explanation: Antecedent infection with campylobacter jejuni is known to be frequently associated with GBS