The smog is essentially caused by the presence of
oxides of sulphur and nitrogen
As we learned
Smog -
Dark fog having condensed water vapour, dust, smoke and gases (SO2, H2S, NO2 etc)
- wherein
Smoke + fog = Smog
Oxides of sulphur and nitrogen manly causes the smog.
Option 1)
Option 2)
Option 3)
oxides of sulphur and nitrogen
Option 4)
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