This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Joint disorders, Subject name: Orthopaedics
A 65 years old lady presented with a swollen and painful knee. On examination, she was found to have grade III osteoahritic changes. What is the best course of action? 
Select and explain. 
A. Conservative management, B. Ahroscopic washing, C. Paial knee replacement, D. Total knee replacement
A: Conservative management
Answer: A: Conservative management 
Explanation: ref : maheswari 9th ed