Watery diarrhea is caused by the infectious disease known as Cholera , which can cause a condition of dehydration and can lead to death if it is untreated. It is caused by a bacterium with a eating food or drinking water and this bacterium is called Vibrio cholerae.
In the 1800 century the Cholera was prevalent in the US with the contaminated water. Ten cases of cholera are reported each and every year in the United State and abroad acquired half of these .
I imagine this is for a job application, c would also be a good option as well but its best to try to resolve the problem on your own and then talking to your boss about it if the issue continues over time.