I'm sorry i do not know the answer, but in the picture you took i noticed how it said hint try clicking on that and I also noticed it said chapter 2 at the top of the page if that is a reading source that has information i would read through that or put a link to that so we can read it and see if it helps us get the most accurate answer.
Answer:
An extremely important byproduct of photosynthesis is oxygen, on which most organisms depend.
Explanation:
Photosynthesis occurs in green plants, seaweeds, algae, and certain bacteria. These organisms are veritable sugar factories, producing millions of new glucose molecules per second.