This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Streptococci, Subject name: Microbiology
Causative agent of acute rheumatic fever - 
Select and explain. 
A. Group 'A' b-hemolytic streptococcus, B. Group-B b-hemolytic streptococcus, C. Group-C b-hemolytic streptococcus, D. Group-D b-hemolytic streptococcus
A: Group 'A' b-hemolytic streptococcus
Answer: A: Group 'A' b-hemolytic streptococcus 
Explanation: Ans. is 'a' i.e., Group 'A' p-hemolytic streptococcus o Acute rheumatic fever is caused by streptococcus pyogenes - group-A Beta hemolytic streptococcus.