Read the given assertion and reason and choose the correct option.
Assertion [A]: UV radiation causes the photo-dissociation of ozone into O2 and O, thus causing damage to the ozone layer.
Reason [R]: The ozone hole has been the major cause of global warming and climate change.
UV radiation does not cause photodissociation of ozone into O2 and O. Instead, it takes part in the formation of ozone in two steps.
O2 ---> O + O
O2 + O ---> O3
Due to certain careless human activities, the ozone layer in the stratosphere has been thinning down in certain areas, creating an "ozone hole". The ozone hole has resulted in rain failure, increased incoming radiation, cancers and a reduction in crop production. Global warming and climate changes are mainly caused due to an increase in the amounts of greenhouse gases in the atmosphere.