Which of the following is characteristic of CFCs? 

A)  CFCs are relatively unreactive compounds. 
B)  Ultraviolet radiation will not cause CFCs to break down. 
C)  CFCs are heavy molecules that will sink in the atmosphere. 
D)  Only UV-B radiation is impacted by CFCs.

CFCs (chlorofluorocarbons) are known to be relatively unreactive compounds, which is one of the reasons they were used as refrigerants, solvents, and propellants. However, this characteristic also makes them very stable in the atmosphere, allowing them to persist for many years and cause damage to the ozone layer. Ultraviolet radiation can cause the breakdown of CFCs, but this process releases chlorine atoms that can react with ozone molecules and deplete the ozone layer. CFCs are also relatively heavy molecules that can sink in the atmosphere and reach the stratosphere where the ozone layer is located. CFCs can impact both UV-B and UV-C radiation, not just UV-B.