When transitioning from a mostly rural to a mostly urban society, it is important to keep sustainability in mind. Try to find ways in which the most energy is conserved, which will increase employment and lower revenue and pollution.
Photosynthesis is when plants turn light from the sun into food (energy). The light from the sun is turned into energy by using chlorophyll. Chlorophyll absorbs blue and red light to turn Co2 and H2o into glucose.
The answer to the question is option C