Answer:
B. Black-eyed Susans and daisies used to be part of the same species. A random mutation in a subset of a population caused one group to release their pollen three weeks before the other, causing interbreeding to cease.
Step-by-step explanation:
Temporal isolation, where temporal relates to time. So temporal isolation is the process where two populations will reproduce at different times/different seasons and therefore cause a split in species. In this case, we see the flowers release pollen at different times and caused a split into two distinct species.