CFCs, or chlorofluorocarbons, contain refrigerants. This means the answer is answer A: refrigerants that contain chlorine but not hydrogen are so stable that they do not break down in the lower atmosphere after being released. The chlorine or bromine reacts with ozone, causing it to change back to oxygen and damaging the ozone layer.
Phew! That’s a long answer!
So, this basically means that a CFC molecule has a very tight bond between all its atoms. It’s like superglue that has dried. You’re not prying that off. No matter how hard you try. When it comes into contact with ozone, the bonds change, and oxygen is produced.
This is why the EPA banned CFCs way back in the 1970s. Sure, we still use a lot of products that damage the earth, but we’re getting better. We’re getting better, and that’s what matters.