question: Q:A 25-year-old man comes to the physician because of left-sided knee pain for 2 weeks. The pain started while playing basketball after suddenly hearing a popping sound. He has been unable to run since this incident. He has asthma, allergic rhinitis, and had a progressive bilateral sensorineural hearing impairment at birth treated with cochlear implants. His only medication is a salbutamol inhaler. The patient appears healthy and well-nourished. His temperature is 37°C (98.6°F), pulse is 67/min, and blood pressure is 120/80 mm Hg. Examination of the left knee shows medial joint line tenderness. Total knee extension is not possible and a clicking sound is heard when the knee is extended. An x-ray of the left knee shows no abnormalities. Which of the following is the most appropriate next step in the management of this patient?? 
  {'A': 'Arthrocentesis of the left knee', 'B': 'Open meniscal repair', 'C': 'Reassurance and follow-up', 'D': 'MRI scan of the left knee', 'E': 'Arthroscopy of the left knee'},