This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Keinbock's disease is osteochondritis of ? 
Select and explain. 
A. Scaphoid, B. Lunate, C. Calcaneum, D. Tibial tuberosity
B: Lunate
Answer: B: Lunate 
Explanation: Ans. is 'b' i.e., Lunate