The correct answer is memory cells.
Vaccination refers to the clinical use of immunization established to artificially assist the body in fighting against the disease. A vaccine against an infection is an amended kind of a natural immunogen that may be the component of the pathogen, a toxin, or even the whole pathogen.
A vaccine does not result in a disease, however, instigates the healthy host to fight against the epitopes of the amended immunogen and produce ample amount of memory cells (T and B cells).
Due to the production of the memory cells, when the body comes in contact with an antigen or immunogen again, then the memory cells generate antibodies quickly and kills the pathogen before it can impart its influence.
