A. Robert Koch
B. Louis Pasteur
C. Edward Jenner
D. Joseph Lister
Explanation: Edward Jenner developed the first successful smallpox vaccine in 1796 using material associated with cowpox.
A. Robert Koch
B. Louis Pasteur
C. Edward Jenner
D. Joseph Lister
Explanation: Edward Jenner developed the first successful smallpox vaccine in 1796 using material associated with cowpox.