Respuesta :
Answer:
option 3- They were exposed to cowpox, and the substance their body produced to fight cowpox also attacked smallpox.
Explanation:
Jenner decided to infect Phipps with the innocuous from the handmaids in order for him to produce antibodies and boost his immunity.
What is vaccination?
Vaccination is the process of giving vaccines to individuals in order to boost their immunity against infections and diseases.
During vaccination, weakened infectious cells are introduced to to the body for the body to produce antibodies against it.
Therefore, Jenner decided to infect Phipps with the inoculum from the handmaids in order for him to produce antibodies and boost his immunity.
Learn more about vaccination at: https://brainly.com/question/2620291
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