You are answering a USMLE-style medical question. Question: A 32-year-old man presents to the emergency department with fever, nausea, and vomiting. The patient states that his symptoms started last night and have persisted to this morning. He has a past medical history of asthma, and his current medications include albuterol and fluticasone. His temperature is 102°F (38.9°C), blood pressure is 110/60 mmHg, pulse is 95/min, respirations are 17/min, and oxygen saturation is 98% on room air. On physical exam, the patient seems uncomfortable. He requests that the lights in the room stay turned off during the physical exam. The patient's cardiac exam demonstrates a normal rate and rhythm, and his pulmonary exam is clear to auscultation bilaterally. Musculoskeletal exam reveals diminished mobility of the neck in all four directions, with flexion of the neck causing the patient discomfort. Lumbar puncture is performed and results are seen below. Cerebrospinal fluid (CSF): Cell count: 175/mm^3 Cl-: 119 mEq/L Glucose: 49 mg/dL Pressure: 150 mmH2O Total protein: 55 mg/dL Which of the following is the best treatment for this patient's most likely diagnosis? Options: A) Acyclovir B) Amphotericin and 5-flucytosine C) Ceftriaxone and vancomycin D) IV fluids and monitoring Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.