In the "herd" strategy for immunization, vaccinations are given . only to individuals who are most likely to be exposed to a disease only to individuals who travel to countries where certain disease are a threat to a large majority of the population the entire population

C. to a large majority of the population.

Explanation:

Immunization can be defined as the process of boosting an individual's immunity or immune system against antigens (immunogen) which cause diseases by the administration of vaccines.

Basically, immunization helps to improve the functions of the antibodies, B cells, T cells etc.

In the "herd" strategy for immunization, vaccinations are given to a large majority of the population in order to protect and prevent the spread of an infectious disease to those who are not immune.