Which example illustrates Darwin's main contribution to the theory of evolution?
An agricultural pest has been exposed to a pesticide that wipes out the entire species.
In a laboratory, a scientist chooses the most intelligent mice and breeds them to advance the species.
When exposed to antibiotics, most bacteria in a population die but some survive and live to reproduce.
In the African savannah, a scientist observes that a wildebeest calf has inherited its coat pattern from its father.

Question

Which example illustrates Darwin's main contribution to the theory of evolution?
An agricultural pest has been exposed to a pesticide that wipes out the entire species.
In a laboratory, a scientist chooses the most intelligent mice and breeds them to advance the species.
When exposed to antibiotics, most bacteria in a population die but some survive and live to reproduce.
In the African savannah, a scientist observes that a wildebeest calf has inherited its coat pattern from its father.