The correct answer is D. Methyl isocynate.
Methyl isocyanate (MIC) is a highly toxic chemical used in the production of pesticides. It is a colorless, flammable liquid with a strong, irritating odor. MIC was the gas that was released from the Union Carbide plant in Bhopal, India, on December 2, 1984, in an accident that killed over 20,000 people and injured over 100,000 others.
Acetylene (C2H2) is a colorless, flammable gas with a sweet odor. It is used in welding and cutting metals, and in the production of other chemicals.
Ethylene (C2H4) is a colorless, flammable gas with a sweet odor. It is used in the production of plastics, synthetic fibers, and other chemicals.
Phenyl isocyanate (C6H5NCO) is a white, crystalline solid with a strong, irritating odor. It is used in the production of polyurethanes, isocyanate-terminated polymers, and other chemicals.