The answer to this is B. Heart Attack. Cardiovascular disease is still known to be one of the main killers of people at present time. Cardiovascular diseases are not usually brought about by the improper disposal of sewage. There are other reasons why people may get this. There are some who have underlying diseases like Diabetes so they are more prone to this condition.
Some people may get this because of their sedentary lifestyle and because they do not get enough exercise. More and more people rely on getting food that can be easily acquired and these foods may not always be healthy. There are different things that can contribute to this disease.