Passive immunity lasts only as long as the antibodies survive in body fluids, and booster shots are needed periodically to build up the passive immunity again. Given these facts, what are needed after antibodies won't survive in body fluids among the following options:
- booster shots
 - Veins and arteries.
 - chicken pox
 - Energy.
 - gun shots
 - kinetic energy
 - diseased tissue
 - turn to a doctor


 

 booster shots        