An organism that lives in or on another organism, often with harmful side effects—but without benefits is a:

That would be a parasitic relationship.  The organism is a Parasite.

Pretty sure this would be b. the rest are trick questions. the bystanders  won't go near you if u have cpr cuffs that could hurt them. the dog will back off because the sound will scare him. and the vomits just a stupid trick. if there is that much slober and vomit on the guy hes either choking on it, or just take off his shirt.