Which of the following describes an example of life coevolving with a change in Earth's systems? A. Large grassland birds developed on several different continents.
B. Many species of reptiles and amphibians evolved gradually over extremely long periods of time.
C. A sudden environmental change triggers a mass extinction of a group of mammal species.
D. Oceans flooded large land areas, creating shallow marine habitats in which animal groups split into different species.