Which instruction indicates a lack of understanding of a nurse teaching a human immunodeficiency virus (HIV) -positive client about strategies to prevent opportunistic infections? a. Rinse cups after washing them with warm soapy water b. Rinse your toothbrush in liquid laundry bleach after every week c. Wash your armpits, groin and genitals with antimicrobial soap twice a day d. Purchase organic, unpasteurized apple cider for your vitamin C requirements