Fact 1: Active immunity results when an immune response to a pathogen produces memory cells.

Fact 2: Vaccination is Active Acquired Immunity.

Given the two facts above, answer the question "What results when an immune response to a pathogen produces memory cells?" with the following options: 
- anemia
 - vaccination
 - kill them
 - competition
 - lie detectors
 - rapid expansion
 - killing insects
 - it needs them


 

  vaccination       