What does the process of photosynthesis produce?

Oxygen.

Explanation:

During the process of photosynthesis, plants break apart the reactants of carbon dioxide and water and recombine them to produce oxygen (O2) and a form of sugar called glucose (C6H12O6).

More info:

Plants are autotrophs, which means they produce their own food. They use the process of photosynthesis to transform water, sunlight, and carbon dioxide into oxygen, and simple sugars that the plant uses as fuel. These primary producers form the base of an ecosystem and fuel the next trophic levels

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explanation:

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