Volpe's Understanding Evolution 7th Edition by Peter Rosenbaum

Exercise 18

There is a major mass extinction currently going on NOW that is different than previous mass extinction. It is happening quicker and it is happening due to the actions of a single species (humans). What of the following is NOT a key stage or pulse in this modern mass extinction event?
A) The advent of agriculture
B) The spread of humans across the globe.
C) The spread of European across the globe.
D) The exponential increase in the human population.