I am not 100% sorry if I am wrong but I think it’s C
The correct answer is - A) Permafrost used to be permanent.
The permafrost used to be permanent until recently, so using certain techniques of building on it functioned properly. But with the climate changes that are becoming more and more evident, the permafrost is no longer permanent, but instead, it is either defrosting in some part of year and then forming again, or has been totally absent from some regions in the present.
That has caused changes in the rules governing building on permafrost. The reason for the changes is that the old techniques do not work properly anymore, and the permafrost changes are making change in the landscape, making big damages on the infrastructure in meantime.
Answer:
Stratosphere
Explanation:
Yes, the ozone is a triatomic molecule that is composed of various oxygen molecules and which are broken by the sunlight to the formation of ozone layer this layer is found in abundance in the Stratosphere the layer above the tropopause that is the region where mixing stops. This layer extends from 30 to 60 kilometers in the stratosphere that absorbs the harmful radioactive substance and also the UV rays that can penetrate the earth and could have caused damage to the life forms on the planet. To date, continuous use and abuse of CFC gas produced by the air conditioners and the methane gas that is a natural greenhouse gas has caused a whole over the arctic circle and part of Russia. The low layers of ozone have been completely depleted due to imbalance of active carbon particles and pollutant matter in the atmosphere the air over the industrial district of china and India is itself an example. Impact of ozone UVa and UVB can be seen in high latitudes but of them, most harmful UVc is restricted by this layer and due to the quality deterioration of ozone is poses grave threats in future
