Respuesta :
Answer:
Option A, Vaccine
Explanation:
In active immunity, antibodies are produced with in the body of an organism by introducing vaccines which is similar to exposing a body to antigen so that it starts producing antibodies in response to them which lasts longlife .
For example – when vaccines of hepatitis A virus is given to a person, the antigens are introduced in an individual’s body which activates the immunity response system and allows the internal self-defense system to produce antibodies that will protect the body lifealong against the hepatitis A virus
