This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
Not seen in faecal pollution - 
Select and explain. 
A. Staphylococcus, B. Streptococcus, C. E. Coli, D. Clostridium perfringens
A: Staphylococcus
Answer: A: Staphylococcus 
Explanation: The primary bacterial indicators of contamination of water are the coliform group. Supplementary indicators include faecal streptococci and sulphite-reducing clostridia(C.perfringens) Park's Textbook of Preventive and Social Medicine, 25th edition, Page No. 780,781