Cellular respiration is
a spontaneous reaction that assembles smaller molecules into bigger molecules.
a spontaneous reaction that breaks down larger molecules into smaller molecules.
a nonspontaneous reaction that assembles smaller molecules into bigger molecules.
a nonspontaneous reaction that breaks down larger molecules into smaller molecules.

The correct answer would be the second option.

Cellular respiration refers to sum total of biochemical reaction which take part in harnessing the energy from food and convert it into ATP.

The process of cellular respiration is spontaneous in nature as change in Gibbs energy is negative for overall reaction of cellular respiration.

Glucose + Oxygen → Carbon dioxide + Water + energy

It can be clearly observed that glucose is broken down into carbon dioxide and water in presence of oxygen.

Thus, the correct answer would be second option.

i think the answer would d

i think its the first one