This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
The cells responsible for long lasting immune protection to a paicular pathogen are called 
Select and explain. 
A. T helper cells, B. B helper cells, C. T memory cells, D. B memory cells
D: B memory cells
Answer: D: B memory cells 
Explanation: Memory B cells are more long-lasting and specific than memory T cells because memory B cells have more robust DNA repair mechanism (which provide ability to maintain somatic hypermutations)