(HFCs) are a group of industrial primarily used for cooling and refrigeration. are entirely man-made. They are primarily for use in refrigeration, air-conditioning, foams and aerosol propellants, with minor as solvents and for fire protection. synthetic lubricants used in stationary HFC-based equipment. were developed to replace stratospheric ozone- substances that are currently being phased under the Montreal Protocol on Substances that the Ozone Layer. HFCs currently represent around 1% of total gases, their impact on global warming can hundreds to thousands of times greater than that of dioxide per unit of mass. Amendment to phase down HFCs under the Protocol entered into force in 2019. Under the countries commit to cut the production consumption of HFCs by more than 80% over the 30 years. all the four options are correct.