The correct option is C Methyl isocyanate (MIC)
The Bhopal gas tragedy was a disaster that resulted from an accident. It happened at a Union Carbide subsidiary pesticide plant in the city of Bhopal, India. On 3 December 1984, the plant released 42 tonnes of toxic methyl isocyanate (MIC) gas, exposing more than 500,000 people to toxic gases. The first official immediate death toll was 2,259.