the answer would be none if the above D.
this is because volcanos pollute the air when the erupt. they dont have a major impact on climate change but they do pollute the air.
industries create major air pollution because they release toxic gasses in the atmosphere like carbon monoxide.
combustion also creates air pollution because fires pollute the air
i am 99% sure it is none of the above but if its not that it might be volcanoes