Atoms, molecules, cell membranes, then cell (in order from smallest to biggest).
Answer:
B. Is what the scientists manipulate in the experiment.
Explanation:
The Independent variable is not dependent, or doesn't rely, on another variable in the experiment. So, it would make the most sense that they would manipulate the Independent so that they can watch and see how the dependent variable reacts to the manipulation, or the change, in the independent variable.
Rattlesnakes, and all snakes, are multicellular.
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