You are answering a USMLE-style medical question. Question: An 83-year-old man is admitted to the hospital with fever, weakness, and decreased responsiveness. He is diagnosed with urosepsis based on urinalysis and culture and started on ceftriaxone and intravenous fluids. By hospital day 3, he is clinically improving. During the evening, the patient becomes irritable. He is talking to someone despite nobody being present in the room. He is easily agitated and attempts to strike a nurse with a remote control to his TV. Subsequently, the patient keeps getting out of bed and trying to walk away despite being a fall risk. Which of the following is the most appropriate next step in management? Options: A) Diphenhydramine B) Lorazepam C) Olanzapine D) Physical restraints Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.