An Acutely Violent Patient Diagnosed with Schizophrenia Received Several Doses

An acutely violent patient diagnosed with schizophrenia received several doses of haloperidol. Two hours later the nurse notices the patient's head rotated to one side in a stiffly fixed position, the lower jaw thrust forward, and drooling. Which intervention by the nurse is indicated?

A) Administer diphenhydramine 50 mg IM from the prn medication administration record.
B) Reassure the patient that the symptoms will subside. Practice relaxation exercises with the patient.
C) Give trihexyphenidyl 5 mg orally at the next regularly scheduled medication administration time.
D) Administer atropine sulfate 2 mg subcut from the prn medication administration record.