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: Microbiology
Bacitracin sensitivity is used to differentiate ? 
Select and explain. 
A. Group A Streptococcus from staphylococci, B. Group A streptococcus from other Beta hemolytic streptococci, C. Group A streptococcus from Gamma hemolytic streptococci., D. Group A streptococcus from Alpha hemolytic streptococci
B: Group A streptococcus from other Beta hemolytic streptococci
Answer: B: Group A streptococcus from other Beta hemolytic streptococci 
Explanation: Ans. is 'b' i.e., Group A streptococcus from other Beta hemolytic streptococci The bacitracin susceptibility test is used to distinguish Group A streptococci, from other streptococci. This test is used to determine the effect of small amount of bacitracin (0.04U) on an organism.