<prompt> Which of the following isare the sourcesources of H2S in the environment?Coral pits SewersSewersCoral pits volcanic eruptionsCoral pits, Sewers Volcanic eruptions  <response>: H2S is formed during coke production, viscose rayon production, wastewater treatment plants, wood pulp production using the sulphate method, extraction process, oil refining and in the tanning industry. Parks Textbook of Preventive and Social Medicine, 25th Edition, Pg 794 