This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
Which prevents apoptosis of Memory B Cells? 
Select and explain. 
A. Platelet derived Growth Factor, B. Nerve Growth Factor, C. Fibroblast Growth Factor, D. IGF
B: Nerve Growth Factor
Answer: B: Nerve Growth Factor 
Explanation: .