Ozone development requires high pressure. It is done during lightening where oxygen is converted to ozone.
The destruction of CFC's will cause good. It will be in favor of ozone.
The ozone development is due to natural factors. UV is main of them.
Ozone depletion is not worse in cities. If you measure the effects of ozone depletion by the number of people affected, there are more people per unit area in cities. Ozone depletion affects every unit area more-or-less equally. Ozone pollution affects cities worst, since NOx is mostly produced by urban and suburban<->urban traffic.
Development of ozone layer helps to avoid the UV from entering.
CFC's are attributed for ozone hole. They react with ozone and deplete it.
An ozone hole developed due to the ozone depletion. It is the lowering of ozone concentration.
The ozone layer is present in the stratosphere. It is because of the perfect conditions there.
Ozone has affected development in a good way. It has protected the earth.
Ozone is present at stratosphere. It is because the suitable conditions are found there.
The layer of ozone does maintain suitable conditions for life. It protects the humans from the UV interaction.
The answer is smog
You can find the ozone layer in the lower stratosphere. It is because ozone find conditions worth creation there.