The pharmaceutical industry argues that because new drugs will not be developed unless heavy development costs can be recouped in later sales, the current 20 years of protection provided by patents should be extended in the case of newly developed drugs. However, in other industries new-product development continues despite high development costs, a fact that indicates that the extension is unnecessary. Which of the following, if true, most strongly supports the pharmaceutical industry's argument against the challenge made above? ['Clinical trials of new drugs, which occur after the patent is granted and before the new drug can be marketed, often now take as long as 10 years to complete.', 'Much recent industrial innovation has occurred in products-for example, in the computer and electronics industries-for which patent protection is often very ineffective.', 'An existing patent for a drug does not legally prevent pharmaceutical companies from bringing to market alternative drugs, provided they are sufficiently dissimilar to the patented drug.', 'No industries other than the pharmaceutical industry have asked for an extension of the 20-year limit on patent protection.']