Pasteur's work with bacteria and disease included work on chicken cholera. During his work, one culture of cholera-causing bacteria spoiled and failed to induce the disease in some chickens Pasteur was trying to infect. Pasteur used these healthy chickens again, this time infecting them with live, healthy bacteria. The chickens did not get sick. He discovered that the weakened bacteria had caused the chickens to become immune to cholera. Pasteur had discovered an idea we use today, to keep us from getting certain disease. He discovered the use of??

A) antibiotics.
B) pasteurization.
C) prescriptions.
D) vaccines.