This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
Most predominant normal flora of human intestine is: 
Select and explain. 
A. Escherichia coli, B. Streptococci, C. Bacteroides, D. Enterococci
C: Bacteroides
Answer: C: Bacteroides 
Explanation: Ans. C. BacteroidesMost common flora in humans is Bacteroides fragilis, which is an anaerobe. Among aerobes, Escherichia coli is the most common bacteria as a part of normal intestinal flora.