This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable diseases, Subject name: Social & Preventive Medicine
At present following types of influenza viruses are circulating in the world, except - 
Select and explain. 
A. H1N1, B. H3N2, C. Type C virus, D. Type B virus
C: Type C virus
Answer: C: Type C virus 
Explanation: INFLUENZA Causative agent : Ohomyxovirus, 3 types: A, B, C Type A: MC cause of outbreaks/epidemics; Only cause of pandemics Type B Type C: Not circulating currently Currently circulating influenza viruses in world H1NI (Type A) - Cause of Swine Flu H2N2(Tpye A) H5N1(Type A) - Cause of An influenza (Bird flu) H3N2 H7N9 H5N6 Type B Ref: Park 25th edition Pgno : 169-171