Consider the following statements: Chlorofluorocarbons, known as ozone-depleting substances, are. used 1. in the production of plastic foams 2. in the production of tubeless tyres 3. in cleaning certain electronic components 4. as pressurizing agents in. aerosol cans Which of the statements given above is/are correct?

1. Chlorofluorocarbons (CFCs) are known ozone-depleting substances (ODS) whose production and consumption have been phased out under the Montreal Protocol. 2. Statement 1 is correct. CFCs were widely used as blowing agents in the production of plastic foams, such as polyurethane, polystyrene (Styrofoam), and phenolic foams, due to their suitable boiling points and inertness. 3. Statement 2 is incorrect. The production of tubeless tyres primarily involves rubber compounding, shaping, and vulcanization. CFCs were not a standard component or processing agent in tyre manufacturing. 4. Statement 3 is correct. Due to their effectiveness as solvents, low toxicity (at ground level), and non-flammability, CFCs (like CFC-113) were extensively used for cleaning sensitive electronic components, precision instruments, and degreasing metals. 5. Statement 4 is correct. CFCs (like CFC-11 and CFC-12) were commonly used as propellants (pressurizing agents) in aerosol cans for various products like deodorants, hairsprays, insecticides, and paints, before being replaced by alternatives. 6. Therefore, statements 1, 3, and 4 describe actual uses of CFCs.