The correct answer is: C. light diesel
Cutback asphalt is a type of asphalt that is made by mixing asphalt cement with a liquid, such as kerosene, gasoline, or diesel fuel. The type of liquid used will affect the properties of the cutback asphalt, such as its curing time and its resistance to water.
Light diesel is the best type of oil to use for rapid curing cutbacks because it has a low viscosity and a high flash point. This means that it will flow easily and will not ignite easily. It also means that it will not evaporate as quickly as gasoline or kerosene, which will help to keep the cutback asphalt from drying out too quickly.
Gasoline and kerosene are both too volatile to be used for rapid curing cutbacks. They will evaporate too quickly, which will make it difficult to control the curing process. They are also more likely to ignite, which can be a safety hazard.
Heavy diesel is too viscous to be used for rapid curing cutbacks. It will not flow easily and will be difficult to mix with the asphalt cement. It will also take longer to cure, which is not ideal for rapid curing applications.
In conclusion, light diesel is the best type of oil to use for rapid curing cutbacks. It has a low viscosity, a high flash point, and it will not evaporate as quickly as gasoline or kerosene.