human
Question: A teacher demonstrates a chemical reaction. A student observes that the test tube in which the reaction occurs becomes warm. What is the source of the thermal energy generated by the reaction?

Choices:
A) energy stored in the reactants
B) breaking bonds of the reactants
C) kinetic energy absorbed by the reaction
D) potential energy absorbed by the reaction
gpt
The correct answer is 0: energy stored in the reactants.