The contact process is used for the industrial production of
The correct answer is: A
Explanation
The contact process is used for the industrial production of sulfuric acid (H2SO4), not any of the options provided. The process involves the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3) which is then absorbed in sulfuric acid to form oleum (H2S2O7). The oleum is then diluted with water to form sulfuric acid.
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