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
Most common CNS manifestation of HIV infection is -a) Vacuolar myelopathyb) Encephalopathyc) Acute meningitisd) Dementia 
Select and explain. 
A. ac, B. bd, C. c, D. d
B: bd
Answer: B: bd 
Explanation: None