Based on the excerpt above, how could other societies use the information Dr. Snow discovered about Cholera?

Excerpt:

"Dr Snow took a sample of water from the pump, and, on examining it under a microscope, found that it contained "white, flocculent particles." By 7 September, he was convinced that these were the source of infection, and he took his findings to the Board of Guardians of St James's Parish, in whose parish the pump fell. Though they were reluctant to believe him, they agreed to remove the pump handle as an experiment. When they did so, the spread of cholera dramatically stopped . . . At the end of September the outbreak was all but over, with the death toll standing at 616 . . . “Broad Street Pump Outbreak.” UCLA Department of Epidemiology. University of California, Los Angeles, School of Public Health. Web. 22 Jun. 2011."

Question:

Based on the excerpt above, how could other societies use the information Dr. Snow discovered about cholera?

A. They would know that cholera, although dangerous, lasts only a few weeks.  

B. They would know that cholera is dangerous and is caused by white, flocculent particles, but they would still have trouble limiting the spread of the disease.

C. Knowing that cholera is spread by air, they could take necessary precautions to ensure that infected people don’t come into contact with healthy people.  

D. Knowing that cholera is spread by contaminated water, they could take necessary precautions to make sure they had clean water supplies.

The correct answer is D

Explanation:

Other societies could use the information provided by snow to investigate all their water sources to ensure that it is free from Cholera.

Cholera is primarily a waterborne disease.

A person may become infected by eating food or drinking contaminated with the cholera bacterium. Cholera epidemics are usually triggered by faeces of the infected which in turn contaminates food and water.