Fact 1: Infection can cause bodily tissues to swell. Fact 2: HIV infection is a chronic lifelong infection. Given the two facts above, what can cause bodily tissues to swell?

Select from the following.
(a). p53;
(b). invisible light;
(c). HIV;
(d). skin;
(e). AIDS;
(f). HPV;
(g). lung;
(h). clouds;
The answer is:
(c).