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: Social & Preventive Medicine
Which of the following lead to an outbreak of Influenza in China in 2013? 
Select and explain. 
A. H7N9, B. H3N2, C. H1N1, D. H2N2
A: H7N9
Answer: A: H7N9 
Explanation: None