Review Question - QID 215763

13-year-old male endorses progressive knee pain over the past 6 months. His pain is worse at night and is not relieved by rest or NSAIDs. He denies fevers, chills, or night sweats. Initial blood work including CBC, CMP, LDH, ESR, and coagulation studies are unremarkable. Figure A is an MRI of his knee. Immunostaining was positive for S-100 protein. Which of the following histological specimens (Figure B-F) is most consistent with his diagnosis?