What compound that results from hydraulic fracturing gives rise to air pollution?

Compound that is release during hydraulic fracturing that gives rise to air pollution is hydrogen sulfide. hydrogen sulfide is a colorless gas that is poisonous and flammable. this will also leads to the formation  of SOx in the air and also to acid rains

It is useful for historians to write narratives so that history can be passed on from their point of view.  think about a story being told in third person, then think about it again being told in first person, by someone who actually experienced the event.

The answer is d) rift