You are answering a USMLE-style medical question. Question: A 42-year-old man presents to your office complaining of right-sided facial swelling that has progressively worsened over the last month after returning from a trip to India. On examination, the patient has an obvious distortion of the facial features on the right without erythema or lymphadenopathy. A neurological exam reveals no deficits. His blood pressure is 115/80 mm Hg, heart rate is 65/min, and the temperature is 37.2°C (98.9°F). The patient states that he has been having trouble chewing his food, but is not experiencing any pain. The patient is up to date on all of his immunizations. Which of the following is the most likely cause of his facial swelling? Options: A) Benign cystic tumor with stroma resembling lymph node tissue B) Benign salivary gland tumor composed of stromal and epithelial tissue C) An infection with paramyxovirus D) Malignant tumor composed of squamous and mucinous cells Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.