How do CFC’s illustrate that technical advances can be a “double-edged” sword?

CFC’s illustrate that technical advances can be a “double-edged” sword as CFC's were made for the advantages but soon or later it came as a disadvantage for environment.

CFC's was discovered with many advantages such as they are stable, non-corrosive, and replacement of harmful ammonia used in refrigerators  and air conditioning systems. But soon it is also discovered that CFC's are destroying  the upper atmosphere layer called ozone, which is a very big disadvantage for us. CFCs are major contributor  to global warming after carbon dioxide.

Hence, it proves that CFC’s shows how technological advancement can be “double-edged” sword.

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.

i think the answer is terrae but not 100 percent sure. ▓▬▬ §