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 "Vaccination  produces" with the following options: 
- memory cells
 - pathogens
 - adrenaline
 - autism
 - warmth
 - Energy
 - rapid expansion
 - positive


 

 memory cells        