Which gas bubbles are being collected? nitrogen, because it is a waste product of photosynthesis

water vapor, because it is a waste product of photosynthesis

oxygen, because it is a waste product of photosynthesis

carbon dioxide, because it is a waste product of photosynthesis

Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2