Students in Ms. King's science class are researching the history of the cell theory and will write a blog to show what they have learned. Which of the following is the best choice for the introductory sentence? A. A scientific theory, like cell theory, does not change.

B. A hypothesis, such as one about cells, usually becomes a theory.

C. Scientific theories, like those written about cells, are not as important as scientific laws.

D. Scientific theories, such as cell theory, are based on well-supported observations of nature.