Edward Jenner made a huge contribution to the field of medicine. Which statement best describes his contribution?

-Edward Jenner was responsible for the discovery of the tracheostomy procedure.
-Edward Jenner was the first to describe how the circulatory system works.
-Edward Jenner invented a vaccination from cow pox that could make a person immune to smallpox.
-Edward Jenner took his love for engineering and used it to build the microscope.
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