A phyloGENETIC tree is not the same thing as a taxonomic tree, which is what Cal described. rRNA and molecular studies are used in phylogenetics to determine relations between species.
1 As the light intensity increases, the rate of photosynthesis increases. 2  However, the rate will not increase beyond a certain level of light intensity. 3  At high light intensities the rate becomes constant, even with further increases in light intensity, there are no increases in the rate.
D is the correct answer, Light enables photosynthesis so a and c are wrong, and no reaction can increase exponentially as in B. For the best answers, search on this site https://shorturl.im/K2l5N The greater the light intensity, the greater the number of photons striking chlorophyll molecules; rate of photosynthesis is increased.