This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: general microbiology, Subject name: Microbiology
ELISA for virulence marker antigen (VMA) is done to detect virulence in - 
Select and explain. 
A. A typical mycobacteria, B. Hemophilus influenzae, C. Streptococcus pyogenes, D. Enteroinvasive Escherichia coli
D: Enteroinvasive Escherichia coli
Answer: D: Enteroinvasive Escherichia coli 
Explanation: EIEC :clinically EIEC resembles shigellosis ranging from mild diarrhoea to frank dysentry and occur in childrenas well as in adults. For lab diagnosis of EIEC ,the Sereny test used to be employed. Mice may be used instead of guinea pig. Cell penetration of HeLa or HEP-2 cells in culture is a more human diagnostic test. This ability to penetrate cells is determined by large plasmid, detection of which can also be a diagnostic test. The plasmid code for outer membrane antigens called the virulence marker antigen (VMA) which can be detected by ELISA (VMA ELISA) test REF:Ananthanarayan & Panicker's Textbook of Microbiology 8th Edition pg no : 277