I think (A) but let someone double check
Humans have once settled in areas that are now covered in glaciers.
The Pangaea Earthquake.
The Green House Effect.
Answer:
Explanation:
The achievement of sovereignty for the Quebec state. The creation of a political and economic association between this new independent state and Canada.
Answer:
The layer of greenhouse gases is permeable to one side and not permeable to another side.
Explanation:
Greenhouse gases such as carbondioxide, methane and water vapors etc formed a layer which allow the sun radiation to the earth surface but when these radiation reflected back, this layer traps these reflected radiation and the radiation remain suspended in air which heat up the particles present in the air and increases the temperature which causes global warming of earth surface. This phenomenon is also called greenhouse effect and it is also very useful in growing crops in cool seasons. So this layer is permeable from one side and not permeable from another side.