The answer would be:
C. Smoke in air causes breathing difficulty in animals.
Read on if you want to know why:
When you talk about biosphere it is referring to the living organisms on Earth. Bio- means "life". When we talk about atmosphere on the other hand, we are referring to the air around us. Atmos- means "vaporous air" around us.
Using those as your clue, take the answer as an example of how to determine what spheres were interacting:
Smoke in air causes breathing difficulty in animals.
Air and animals (living organisms)
So in short we know that the atmosphere and biosphere are interacting in this scenario.