Natural springs hope this helps :D
Answer:
A
Explanation:
Because b,c,d can be proven
while a is not proven
Answer:
C. control rods
Explanation:
Devices that absorb neutrons and are used to control the speed of a fission reactor are called control rods. They are used in nuclear reactors to control the fission rate of uranium and plutonium. They are composed of chemical elements that are capable of absorbing many neutrons .
hope this helps :)
Answer:
A. Vaccines
Explanation:
These are meant to prepare the body for the possibility of infection by building up immunity.
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