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: Unknown
This disease is 
Select and explain. 
A. Osteochondrosis of the lunate, B. Osteochondrosis of the navicularq, C. Tuberculosis of the scaphoid, D. Syphilitic dactylitis
B: Osteochondrosis of the navicularq
Answer: B: Osteochondrosis of the navicularq 
Explanation: Osteochondrosis of the tarsal navicular (Kohler's disease) is characterised by aseptic necrosis of the Navicular bone causing a painful limp in a child usually 4-10 years of age.