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
All are true about EHEC, except: 
Select and explain. 
A. Sereny test is positive, B. Ferments sorbitol, C. Causes HUS, D. Elaborates shiga like exotoxin
A: Sereny test is positive
Answer: A: Sereny test is positive 
Explanation: Sereny Test is given only by EIEC. Ref: Text Book of Microbilogy By Ananthanarayan, 6th Edition, Page 257 ; Harrison's Principles of Internal Medicine, 14th Edition, Page 938 and 15th Edition, Page 955