This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Orthopaedics
Which is the investigation of choice for a sport injury of the knee? 
Select and explain. 
A. Ultrasonography, B. Plain radiography, C. Arthrography, D. Arthroscopy
D: Arthroscopy
Answer: D: Arthroscopy 
Explanation: (d) Arthroscopy- The usual protocol for sports injury in a suspected case is to diagnose the injury by MRI and if diagnosis is in doubt than arthroscopy can confirm the lesion.