What was Darwin’s conclusion about the shells in Santiago

Darwin noticed that the plants and animals on the different islands also differed. For example, the giant tortoises on one island had saddle-shaped shells, while those on another island had dome-shaped shells (see Figure below). People who lived on the islands could even tell the island a turtle came from by its shell.

Explanation:

After looking at the graph represented above, I think I habe recognized the correct answer,  so the statement  which would best predict the population in generation 4 is being shown in the first option : The nonresistant aphid would become extinct. As you can see from the tree pictures, nonresistant ones gradually become lower and lower and in the last one it has the same weak position as resistant in the first picture, then I would say that nonresistant will expire soon.

Hope that helps!