I believe the answer is PREZYGOTIC isolating mechanisms
Answer:
Coniferous forest biome has more precipitation to the Deciduous forest biome.
It's definitely not A. since the toxins would kill butterflies. B. doesn't seem relevant. C. doesn't make sense because the toxins in the pollen are to protect the corn not to make new strains. So, the answer would be D. The carbon dioxide level would increase in the area. Hope this helps!
