C. theory is the answer to your question
Channel proteins is the answer to your question
Answer:
Different brands of nail polishes used by Sarah.
Explanation:
While conducting an experiment two different variables are considered namely dependant variable and independent variable. The variable which is continuously changed to see the effects is called as independent variable and the variable which is being tested is called as dependant variable.
In the given scenario, Sarah want to know best brand of nail polishes which lasts longest without chipping. Thus the different brands of nail polish used by her is considered as independent variable.
