Whooping cough is a very infectious disease of the gas exchange system, caused by the bacterium $\text{Bordetella pertussis}$. Which method protects infants from whooping cough and lowers the likelihood of developing this disease later in life?
- Aa short course of more than one type of antibiotic
- Ba six month course of one type of antibiotic
- Cinjections of antibody specific to $\text{Bordetella pertussis}$
- Dinjections of dead $\text{Bordetella pertussis}$ bacteria