求助一道摸不到头脑的逻辑题~~

How dose a building contractor most readily prove compliance with the building codes governing new construction?By using those established technologies that the authors of the codes had in mind when setting specifications. This , unfortunately, means that there will never be any significant technological innovation within the industry.

Which of the following, uf true,cast the most serious doubt on the conclusion above？

答案是：What are now regarded as established technologies were once so innoative that the authors of the codes the applicable could not have foreseen them.

为什么是削弱阿？我怎么觉得没什么关系呢？