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A 14-year-old girl comes in with right knee pain after a club soccer game. She does not recall a specific fall or collision injury nor a “pop” sensation. The pain started after a run she made down the field during the 4th quarter that did involve some cutting maneuvers. She did complete the game, although she had increasing pain and swelling as the quarter went on. On exam, she has medial joint line tenderness, a moderate effusion, and pain with passive flexion and extension of the knee. 

Which of the following tests do you most expect to be positive / diagnostic?