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: Medicine
Most common complication of rubella- 
Select and explain. 
A. Polyarthritis, B. Encephalitis, C. Orchitis, D. Thromobocytopenia
A: Polyarthritis
Answer: A: Polyarthritis 
Explanation: None