CAN SOMEONE PLEASE HELP OUT

The answer would be C. or the third answer

Plants use sunlight and water to make food, or sugars called glucose. In the process they they take in Co2 and outtake O2. This is how Co2 (what we breath out) is cycled back to O2 (what we breath in).

where is the scientific experiment?

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.