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: Social & Preventive Medicine
Marker of fecal contaminatin is – 
Select and explain. 
A. Ascaris, B. E. coli, C. guinea worm presence, D. Balantidium coli
B: E. coli
Answer: B: E. coli 
Explanation: None