Concept:Cholera is a disease spread through contaminated water and poor sanitation, so prevention focuses on cleanliness.Explanation:Cholera spreads when germs enter food or water from human waste.Keeping our surroundings clean helps stop the germs from reaching water and food.Eating a balanced diet, caring for our bodies, and immunization do not directly stop the spread of cholera in the environment.Answer:B. keeping our surrounding clean