Critical Reasoning (CR) | A worldwide ban on the production of certain ozone-destroying chemical

IMO E
A worldwide ban on the production of certain ozone-destroying chemicals would provide only an illusion of protection. Quantities of such chemicals, already produced, exist as coolants in millions of refrigerators. When they reach the ozone layer in the atmosphere, their action cannot be halted. So there is no way to prevent these chemicals from damaging the ozone layer further.

Which of the following, if true, most seriously weakens the argument above?


(A) It is impossible to measure with
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