When dead plants decompose and nitrogen is returned to the soil, the interaction is between which two spheres?

A. biosphere and atmosphere

B. geosphere and atmosphere

C. atmosphere and geosphere

D. biosphere and geosphere

I think it's d but I'm not sure

D. biosphere and geosphere

Explanation:

Biosphere is the sum of all the ecosystem. The biosphere house all the living things. The biosphere is composed of recycling of matter and the abundant of various factors like sunlight and oxygen that can keep life. Water is another major factor that contribute to life existence. Other elements like phosphorus, nitrogen, oxygen and hydrogen contributes to the building block of life in the form of carbohydrate, fats, protein and lipids.

The geosphere compose of the lithosphere, hydrosphere and the atmosphere and this is strictly the lifeless earth.

The interaction whereby dead plant (biosphere) decompose to add nitrogen to the soil (Geosphere) is an interaction between biosphere and geosphere.