OG12 D40

yunshishow

In 1995 Richard Stallman, a well-known critic of the patent system, testified in Patent Office hearings that, to test the system, a colleague of his had managed to win a patent for one of Kirchhoff’s laws, an observation about electric current first made in 1845 and now included in virtually every textbook of elementary physics.

(A) laws, an observation about electric current first made in 1845 and
(B) laws, which was an observation about electric current first made in 1845 and it is
(C) laws, namely, it was an observation about electric current first made in 1845 and
(D) laws, an observation about electric current first made in 1845, it is
(E) laws that was an observation about electric current, first made in 1845, and is
答案选A。OG说E答案is违背了平行原则，is前面是不是应该加上that才平行？还有OG说E答案在first made in 1845前后加逗号歪曲了句意，但是我觉得意思上并没有什么变化啊。

gth1630

and后面加is改成被动了吧

mongmong

is拿掉为了和 first made in 1845平行，逗号要拿掉为了不引起“first made in 1845”是修饰 electric current的误会