Q: You are presented with the quiz "What infects and destroys the brains behind immune response?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "hIV infects and destroys helper T cells" and "helper T Cells Helper T cells are the brains behind immune response". So, what's the best answer to the question?

Choose your answer from: (1). feet. (2). p53. (3). cancer. (4). HIV. (5). acid. (6). fungus. (7). HPV. (8). host.
A:
(4).