a. Oral Sex - this still causes transfer of sexual fluids which can spread HIV. Technically if sexual fluids come in contact with toilet seats or clothing (underwear, etc), than HIV can be spread through those. But the chances of contracting HIV must be slim for those options since the fluids need to find a cut or an open blood vessel to enter.
You should start with listing the different ways you want to test them. Then each paragraph should talk about each different method and the results. Hope this helps.