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
A person returns to Delhi from Bangladesh after 2 days and has diarrhoea. Stool examination shows RBC's in stool. The likely organism causing is - 
Select and explain. 
A. Enteropathogenic E. Coli, B. Enterotoxigenic E. Coli, C. Salmonella typhi, D. Shigella dysenteriae
D: Shigella dysenteriae
Answer: D: Shigella dysenteriae 
Explanation: None