Imported plants and animals in hawaii have a. caused native species to die out. b. increased the native bird species. c. improved soil fertility. d. increased crop yields.

When a non-native or a foreign plant or animal is introduced in a new area, it affects the survival of the native animals that dwell there. The non-native plant or animal will compete with the native species for nutrients, water, space, food and shelter. Since the non-native animals will lack natural predators in the new habitat, they'll thrive in number. This uncontrolled competition of the non-native species with the native species will eventually leading to the death of the native species.

B

Explanation:

they deliver oxygen to the blood