one question

perfection

16. Originally developed for detecting air pollutants,a technique called proton-induced x-ray emission,which can quickly analyze the chemical elements in almost any substance without destroying it, is finding uses in medicine, archaeology, and crimi-nology.
(A) Originally developed for detecting air pollutants,a technique called proton-induced x-ray emis-sion, which can quickly analyze the chemical elements in almost any substance without destroying it,
(B) Originally developed for detecting air pollutants,having the ability to analyze the chemical elements in almost any substance without destroying it, a technique called proton-induced x-ray emission
(C) A technique originally developed for detecting air pollutants, called proton-induced x-ray emission, which can quickly analyze the chemical elements in almost any substance without destroying it,
(D) A technique originally developed for detecting air pollutants, called proton-induced x-ray emission, which has the ability to analyze the chemical elements in almost any substance quickly and without destroying it,
(E) A technique that was originally developed for detecting air pollutants and has the ability to analyze the chemical elements in almost any substance quickly and without destroying the substance, called proton-induced x-ray emis-sion,

答案是A,A中的 it 指代没有问题？
还有象这种很长的划线题，有什么好的方法？谢谢。

lyricling

A项it指代substance应该没有问题。
像这种被几个逗号分隔的长划线的句子，可以从句子结构入手，找到主谓结构，再看修饰语成份。往往错误选项都是将修饰语成分的位置乱放。

1stzhang

it 就是指带前面的any substance

tocean0222

我觉得这种题关键还是要看清楚，句子的各部分的成分，Originally developed for detecting air pollutants做什么？那个是主句？那个是从句？如果是定语从句，它修饰对象又是什么？这样才能比较快的判断个部分的位置和用法是否有误；

仅供参考！