Diseases or other disorders can be passed down through your family so you need to know your families history to know if you are at an increased risk.
Most of these I would advise you not to handle food with, but the most seriousness of these diseases is Typhoid Fever. Typhoid Fever is obtained by food an infectious person handles. The answer is C.
Mostly because sometimes the people are doing something just because of the impulse and they would not think it over therefore making poor choices <span />
