This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Chemotherapy, Subject name: Pharmacology
Which is the integrase inhibitor used in treatment of HIV? 
Select and explain. 
A. Raltegravir, B. Indinavir, C. Lopinavir, D. Fosamprenavir
A: Raltegravir
Answer: A: Raltegravir 
Explanation: Raltegravir (RAL, Isentress, formerly MK-0518) is an antiretroviral drug used to treat HIV infection, the integrase inhibitor.Raltegravir targets integrase, an HIV enzyme that integrates the viral genetic material into human chromosomes, a critical step in the pathogenesis of HIV. The drug is metabolized away glucuronidation. REFERANCE:en.wikipedia.org