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
Streptococcus is classified based on - 
Select and explain. 
A. M protein, B. Cultural characteristics, C. Bile solubility, D. Cell wall carbohydrate
D: Cell wall carbohydrate
Answer: D: Cell wall carbohydrate 
Explanation: Ans. is 'd' i.e., Cell wall carbohydrate