2. What was in Jenner’s smallpox vaccine? A. smallpox pathogens
B. antitoxins
C. cowpox pathogens
D. antibiotics
 
3. Why did milkmaids who had developed cowpox not get sick with smallpox?
 
4. Why did the boy whom Jenner exposed to smallpox not get the disease?

5. Based on the history above, what would have happened to the boy if he were exposed to smallpox five years later? Why?
L lol

2) cowbox pathogens.

3) due to cowpox and smallpox being quite similar, the body was able to recognise the similar smallpox virus from its antigens and was able to fight the disease effectively.

4) because he was vaccinated with cow pox pus.

5) He will not be infected by smallpox due to the vaccination he had from Jenner, who later on proved the immunisation by inoculating the boy with small pox 6 weeks later, which, had no affect later on in his life.

Imma gonna say go with the very first answer (: