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
Which radiological feature would help differentiate rheumatoid ahritis with SLE? 
Select and explain. 
A. Erosion, B. Juxta-aicular osteoporosis, C. Subluxation of MCP joint, D. Swelling of PIP joint
A: Erosion
Answer: A: Erosion 
Explanation: Answer is A (Erosion): SLE is characterized by non erosive ahritis while bone erosions are characteristic in Rheumatoid Ahritis.