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
Which HIV-virus is more dangerous: 
Select and explain. 
A. HIV-1, B. HIV-2, C. Both are same, D. It depends on host factors
A: HIV-1
Answer: A: HIV-1 
Explanation: Ans. a. HIV-1