The correct answer is C. Sulphur.
Vulcanization is a chemical process for converting natural rubber or other elastomers into more durable products. It is achieved by heating rubber with sulfur, which causes the rubber molecules to crosslink with each other, making the rubber stronger and more resistant to heat, cold, and wear.
Nitrogen, silicon, and alcohol are not used in the vulcanization process. Nitrogen is an inert gas that does not react with rubber. Silicon is a semiconductor that is not used in the vulcanization process. Alcohol is a solvent that is not used in the vulcanization process.
The vulcanization process is a critical step in the production of rubber products. It is used to make rubber products that are strong, durable, and resistant to wear.