Answer:
selective pressure
Explanation:
selective pressure means a cause that reduces success in ones portion or/of a population so that can be the same for bird if a plant disease found its way to a plant the a bird eats.
Use your imagination, people here most likely wont answer an essay for you. Follow the instructions and again use your imagination.
21. B. recessive
22. D. DD and dd
23. D. FF and ff
The answer is 5 kingdoms:)