Which of the following methods has the highest risk of transmitting HIV? A. oral sex B. sharing needles C. sweat D. preseminal fluid

I disagree with the answer above, because 'oral sex', besides sweat, has the least possibility of transmitting HIV, because saliva has the ability to destroy those cells in the mouth. The highest risk and the correct answer would be B, if by needles you mean those in syringes used in medicine or by drug addicts, because of course, there are traces of blood in those needles, and HIV is transmitted primarily through blood. Also, if you don't mean those needles, then the correct answer would be D, preseminal fluid. It can contain small amounts of HIV, so there is a potential risk of transmitting it.