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: Microbiology
True about helicobacter pylori are all except - 
Select and explain. 
A. Urea breath test is diagnostic, B. Grain negative, flagellate bacilli, C. Risk factor for development of adenocarcinoma of stomach, D. It provides life long immunity
D: It provides life long immunity
Answer: D: It provides life long immunity 
Explanation: None