What is the acceptable level of coliform bacteria colonies in drinking water,according to the World Health Organization? 

A)  0 per 100 millilitres of water sample 
B)  5 per 100 millilitres of water sample 
C)  10 per 100 millilitres of water sample 
D)  100 per 100 millilitres of water sample

The acceptable level of coliform bacteria colonies in drinking water, according to the World Health Organization is 0 per 100 millilitres of water sample. Any presence of coliform bacteria in drinking water indicates that the water has been contaminated with faecal matter and poses a health risk. Therefore, the goal is to have no presence of coliform bacteria in drinking water.