The answer is B
Here is a small experiment you can do to test this.
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Put a pot of water on the stove and bring it to a boil. Take a dry lid and cover it for a minute, and lift the lid up. What happens?
What should happen is that the water droplets run down the lid and fall back into the pot.</span>
C Chromosomes break at centromeres,and sister chromatids move to opposite ends of the cell.
In the experiment, the independent variable is the drug amount. Experiment group is given certain amount of drug, control group is not given the drug. The dependent variable is the body fat. I think you means the control is the living environment including food and water.