Hey there,
Your answer is:
<span>Hydrogen turns into helium.
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Hope this helps...Good Luck
Answer:
The answer is B, extensive research of an individual organism over many years.
Explanation:
The question is asking, what best describes Darwin's studies that led to the theory of evolution, it would be a lot of research over a long period of time. Think, if you were to do a school project, would you get your best results over a short or long period of time with little or a lot of evidence/research? So, B is the best answer, I believe.
(PLEASE BRAINLIEST)