You are answering a USMLE-style medical question. Question: A 56-year-old woman is brought to the emergency department because of a 2-day history of fever, chills, nausea, and flank pain. She has multiple sclerosis and a chronic indwelling bladder catheter for neurogenic bladder dysfunction. One week ago, she was discharged from the hospital after treatment for a multiple sclerosis flare. Her temperature is 39.3°C (102.8°C). Physical examination shows marked tenderness in the right costovertebral area. Urine cultures grow a non-lactose fermenting, oxidase-positive, gram-negative rod. The causal organism of this patient's current condition most likely produces which of the following substances? Options: A) Lipoteichoic acid B) K capsule C) Toxin B D) Pyoverdine Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.