Which piece of information provided the stimulus for the shift from traditional classification to modern classification?
a an understanding that organisms have not changed over time
b an understanding that species are not related to one another
c an understanding that species share a common ancestor
d there is no difference between the two systems

The information for the shift from tradition to modern classification is letter c. an understanding that species share a common ancestor. The evolution of species came from traditional classification then came out to evolve as to what it is seen today. They have common ancestors if you will look at their similarities but with the advent of evolution, there are already variation of these species.

The correct answer is c.