A nurse is caring for a client who received succinylcholine IV bolus during an abdominal surgery. The client develops malignant hyperthermia. The nurse should administer which of the following medications?

A. Naloxone: Naloxone is an opioid antagonist used to reverse opioid overdose. It has no effect on malignant hyperthermia, which is a severe reaction involving muscle rigidity and hypermetabolism due to certain anesthetic agents. B. Baclofen: Baclofen is a muscle relaxant used to treat spasticity from conditions like multiple sclerosis. It does not treat malignant hyperthermia and is not effective in reversing the underlying hypermetabolic crisis. C. Dantrolene: Dantrolene is the antidote for malignant hyperthermia. It works by directly relaxing skeletal muscles and reducing excessive calcium release in muscle cells, which is the core problem in this life-threatening condition. D. Acetylcysteine: Acetylcysteine is used primarily for acetaminophen toxicity and as a mucolytic. It has no role in treating malignant hyperthermia and would not address the muscular or metabolic symptoms involved.