D.theory.
Hypothesis is an idea or explanation of something that is based on a few know facts but that has not yet been proved to be true or correct.
While a theory is a formal set of ideas that is intended to explain why something happens or exists.
A vaccine can help keep people healthy and protect them from a certain virus. For example people in the United States get the flu shot when they get this shot the vaccine wont magically get rid of the virus but rather help them fight it off and protect them in the future if they keep up to date getting the vaccine
Answer: What are you asking??
Adaptation is the correct answer
