Through the topic of the graphic information can be seen: the water mollusc and aerobic bacteria contained in the fashion film, with different wavelengths of light beam irradiation of different parts of the water mollusc. Microscopic observation found that aerobic bacteria are concentrated only in the wavelength of 770 nanometers and 390 nanometers or so, indicating that here is conducive to photosynthesis to produce oxygen; and 560 nanometers or so, there is no aerobic bacteria (oxygen to survive), indicating that this wavelength is not conducive to photosynthesis. It can be concluded that the wavelength of light is different, the strength of photosynthesis is different. The absorption of carbon dioxide by photosynthesis cannot be proved in this experiment.
Therefore: B.