use an insulated cup rather than a paper cup change the amount of hydrogen peroxide used take a picture of the cup after the reaction took place use a thermometer to measure the change in temperature
I gave my students this multiple choice question: Alicia put hydrogen peroxide and yeast in a paper cup. The paper cup felt hot, and she concluded that a reaction occurred that gave off heat. What else could Alicia do to get a more accurate conclusion?

Only one answer is correct among these 4 choices:
- use an insulated cup rather than a paper cup
- change the amount of hydrogen peroxide used
- take a picture of the cup after the reaction took place
- use a thermometer to measure the change in temperature

Could you tell me which one is correct?

use a thermometer to measure the change in temperature