The nurse is caring for an immunosuppressed pediatric client who reports soreness in his mouth and refuses to eat. Inspection of his mouth reveals a white, milky plaque that does not come off with rubbing. The nurse should anticipate which drug to be administered to this client?

A. Nystatin is an antifungal medication used to treat oral candidiasis (thrush), which is consistent with the client's symptoms of soreness in the mouth and the presence of a white, milky plaque that does not rub off. B. Amoxicillin is an antibiotic that treats bacterial infections but would not be effective against fungal infections like oral thrush. C. Metronidazole is an antibiotic and antiprotozoal medication, which is not appropriate for treating oral candidiasis. D. Acyclovir is an antiviral medication used to treat infections caused by certain viruses, such as herpes, and is not effective for fungal infections like thrush.