急！prep1-81再问，关于系动词和助动词

81. (28921-!-item-!-188;#058&003760)

In the major cities of industrialized countries at the end of the nineteenth century, important public

places such as theaters, restaurants, shops, and banks had installed electric lighting, but electricity

was in less than one percent of homes, where lighting was still provided mainly by candles or gas.

(A) electricity was in less than one percent of homes, where lighting was still

(B) electricity was in less than one percent of homes and lighting still

(C) there were less than one percent of homes with electricity, where lighting was still being

(D) there was less than one percent of homes that had electricity, having lighting that was still

(E) less than one percent of homes had electricity, where lighting had still been

(B) and lighting still provided省略了was,  因为这里was作为助动词,而前一个并列句的was是系动词,

功能不同,不能省略.

这里我不是很清楚啊，能不能请大家指点一下，不都是be动词吗？省略与否这个是如何理解的呢，急~~谢谢大家了

B 中 lighting [was] still was 表被动，又有and连接、lighting做主语，不管前面一句是什么都肯定不能省的啦，（我不知道你的参考解释为什么扯上前一句，哪怕前一句的was也表被动，都不能省，因为and后已经有新的主语了）。

恕我冒昧，lz一定是一下子题目做的太多了，才糊涂想不通的。如果你放下这道题两天，回头再看一遍，我想一定会觉得没可能是B。。。