Chemical changes occur as energy is transferred when molecules- - or - to form one or more new substances

Correct options are C. As food is digested, molecule bonds are broken, allowing new molecules to form that can be used by our bodies.

D. Energy stored in organic fuels are used for heat and electricity/ When batteries are connected to a circuit, a reaction occurs inside the cell producing electrical energy.

Explanation:

The breakdown of food leads to the release of chemical energy which was first stored in food. This energy is used to drive necessary functions of the body. A series of chemical reactions are involved in the breakdown of food and changing them into useful components for the cell.

Chemical energy is stored in circuits. When the battery is connected to a circuit, the chemical energy gets transferred into electrical energy.

change, combine

positive reinforcement? ?