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
True about E. coil is - 
Select and explain. 
A. Sereny test is done to diagnose Enterotoxigenic E.coli (ETEC), B. Enteropathogenic E. coli (EPEC) are also enteroinvasive, C. UTI is caused by single serotype at a time usually, D. E. coli is the most common causative organism to infect burn wounds
C: UTI is caused by single serotype at a time usually
Answer: C: UTI is caused by single serotype at a time usually 
Explanation: None