The system of patent-granting, which confers temporary monopolies for the exploitation of new technologies, was originally established as an incentive to the pursuit of risky new ideas. Yet studies of the most patent-conscious business of all-the semi-conductor industry-suggest that firms do not necessarily become more innovative as they increase their patenting activity. Ziedonis and Hall, for example, found that investment in research and development (a reasonable proxy for innovation) did not substantially increase between 1982 and 1992, the industry's most feverish period of patenting. Instead, semiconductor firms simply squeezed more patents out of existing research and development expenditures. Moreover, Ziedonis and Hall found that as patenting activity at semiconductor firms increased in the 1980's, the consensus among industry employees was that the average quality of their firms' patents declined. Though patent quality is a difficult notion to measure, the number of times a patent is cited in the technical literature is a reasonable yardstick, and citations per semiconductor patent did decline during the 1980's. This decline in quality may be related to changes in the way semi-conductor firms managed their patenting process: rather than patenting to win exclusive rights to a valuable new technology, patents were filed more for strategic purposes, to be used as bargaining chips to ward off infringement suites or as a means to block competitors' products.
The passage makes which of the following claims about patent quality in the semiconductor industry?

关键词patent quality,题目问的主语也是patent quality,不是patent 定位到 Though patent quality is a difficult notion to measure,...t did decline during the 1980’s. This decline in quality may be related to changes in the way semiconductor firms managed their patenting process: rather than... suites or as a means to block competitors’ products. 选项A 虽然patent的质量是个比较难去鉴定的东西,但是一个专利被technical literature引用到的次数是个合理的衡量方法,并且每个semiconductor patent被引用到的在1980‘s期间确实下降了,那么1980s'前起是比1980后期(a decade later)质量高,正确 选项B it是指patent quality,质量和授予的专利数量没关系 文章未提及 选项C patent quality 和Rand D花费的change方式一样 文章未提及 选项D patent quality is not adequately discussed in the industry’s technical literature.在作品里面引用的是patent,不是patent quality 选项E patent quality was measured by inappropriate means文章未提及

