Vaccination prevents whooping cough in infants Steps:

• Identify the goal: protect infants from infection and reduce future risk, pointing to immunization, not treatment.
• Eliminate antibiotics (A, B): they treat active infections but don't prevent disease in unexposed infants.
• Compare vaccine types: whooping cough vaccines use inactivated (dead) bacteria to safely stimulate immunity without causing illness.
• Select C: dead bacteria provide antigens for immune response, conferring long-term protection.

Why C is correct:

• Inactivated vaccines, like the whole-cell pertussis vaccine, introduce dead Bordetella pertussis to trigger antibody production without infection, per vaccine immunology principles.

Why the others are wrong:

• A: Antibiotics treat symptoms post-infection but offer no preventive immunity.
• B: Prolonged antibiotics suppress bacteria temporarily but don't build lasting immune memory.
• D: Live bacteria injections would cause the disease, not protect against it.

Final answer: C