This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
The organism that most commonly causes infective endocarditis is 
Select and explain. 
A. Streptococcus mitis, B. Streptococcus viridians, C. Staphylococcus aureus, D. Staphylococcus pyogens
B: Streptococcus viridians
Answer: B: Streptococcus viridians 
Explanation: Streptococcus sanguis is most common species in Viridans streptococcus to cause infective endocarditisReference: Jawetz, Melnick, & Adelberg's Medical Microbiology; 27th edition