It was clearly Punctuated Equilibrium.
Multiple Choice answers are always about the 'most correct' option; sure the diagram shows divergent evolution, but it also provides us information regarding the numerous generations that the orginal species remained unchanged for, as well as indicating the generation that contained a mutation in its population and then finally the mutation becoming the dominant variant species in the next immediate generation.
Since it shows
1) Dominant variant species changed over time (divergent evolution)
2) Original species remained unchanged for a total of ____ generations, before the dominant variant within the popuation evolved in 1 single generation
Therefore punctuated equilibrium ftw.