This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
Which of the following bacteria shows this test positive? 
Select and explain. 
A. E coli, B. Klebsiella, C. Proteus mirabilis, D. Proteus Edwardsiella
A: E coli
Answer: A: E coli 
Explanation: Klebsiella,Proteus mirabilis show indole test negative showing yellow ring Red ring-positive- e.g.: E coli, Proteus other than mirabilis, Edwardsville Ref: Textbook of Microbiology Baveja 5th ed Pg 53