After Reading the Paragraphs Below, Answer the Question(s) That Follow(s)

After reading the paragraphs below, answer the question(s) that follow(s) .
Scientists believe that a shift from pollination by insects to pollination by birds occurred several times over the course of angiosperm evolution. Two researchers designed an experiment to investigate how these shifts might evolve using two species of monkey flower (Mimulus spp.) . M. lewisii has violet-pink flowers and is pollinated by bumblebees. M. cardinalis has orange-red flowers and is pollinated by hummingbirds.
The researchers switched flower-colour genes between the two species. As a result of the gene transfer, they produced a variation of M. cardinalis with dark pink flowers (instead of the original orange-red) . The new variety of M. lewisiis had orange flowers (instead of the original violet-pink) . Plants of both genetically altered varieties were placed in their original habitats and observed. The genetically altered variety of M. cardinalis was visited by bumblebees 74 times more often than plants with the original colour flowers. The genetically altered variety of M. lewisii was visited by hummingbirds 68 times more often than plants with the original colour flowers.
-A general conclusion of this study would be that

A) a relatively small change (a single gene) can lead to a relatively major ecological change.
B) a relatively small change (a single gene) has little ecological impact; many genes must be affected to achieve ecological impact.
C) orange is always the best colour for a flower.
D) pink is always the best colour for a flower.