the system primary function is to remove subtances from the blood in the form of urine to regulate various metabolic proceses

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.