PLZ HELPP I WILL GIVVE BRANLIEST IF FAST AND CORRECT Which letter represents the common ancestor of Ray-finned fish and rabbits?

Abiologist counts the number of rabbits in a population each year and observes a decrease in population. since the coyote population has exploded, the biologist concludes that the coyote population has had a negative interaction with the rabbit population. which describes the biologist’s actions? a.) experimentationb.) inferencec.) observationd.) interacting