Final answer:
The nurse should administer N-acetylcysteine (NAC) to a child who has ingested a bottle of acetaminophen, as it is the antidote for acetaminophen toxicity.
Step-by-step explanation:
If a child is in the emergency department after ingesting a bottle of acetaminophen, the nurse should plan to administer N-acetylcysteine (NAC) which is option c. NAC is the antidote for acetaminophen toxicity and works by replenishing glutathione reserves, which help in detoxifying the harmful NAPQI metabolite of acetaminophen that accumulates in the liver during an overdose. Other options such as activated charcoal, naloxone, vitamin K, and flumazenil are not appropriate for treating acetaminophen overdose.