Which of the following is not a characteristic of the northern boreal forest (taiga) biome?
a. prolonged winters (> 6 months)
b. extreme temperatures (-70 to +30 oc)
c. thin, nutrient poor soils
d. high biodiversity in the understory

d. High biodiversity in the understory.

Explanation:

The taiga or boreal forests are the largest biome in the world. These can be found in the regions of North America, Alaska, and United States. These regions exhibit extreme weather conditions. Typically long winters and moderate to high precipitation. The soil is permafrost and nutrient poor as no new organic matter can be added up to the soil due to it's freezing condition. The plant growth is scanty and biodiversity is low because organisms are incapable of surviving in the harsh weather conditions.

thinking it would be d not too sure but i think it's right

a. an idea which cannot be disproven!

explanation: