Hello Everyone!
Let's tackle this question, one thing at a time, and narrow it down to the right choice quickly! To begin, let's take a quick look at the question and highlight any major differences in orange:
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 had been less than 1 percent of homes with electricity, where lighting was still being
(D) there was less than 1 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
While there are a lot of things we could focus on, there are 2 major ones that jump out:
1. was/had been/had
2. was still/still/was still being/was still/had still been
Since both of these deal with verbs, let's start our focus there. If we look at the entire sentence, we can gather clues as to which verb tense we'll need to use:
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.
The events go in a certain order, which requires certain verb tenses:
Public spaces install electric lighting --> electricity is in less than 1 percent of homes + lighting is still done by candles and gas
The earliest event (public spaces install electric lighting) needs to use past perfect "had installed," which it does. The other two events happen later, AND AT THE SAME TIME, so they both need to use past tense. They should also be written using parallel structure. Let's see which options handle this correctly, and eliminate the ones that don't:
(A) electricity was in less than one percent of homes, where lighting was still provided --> OK
(B) electricity was in less than one percent of homes and lighting still provided --> WRONG (needs to have the verb "was" in front of "provided" to work.)
(C) there had been less than 1 percent of homes with electricity, where lighting was still being provided --> WRONG
(D) there was less than 1 percent of homes that had electricity, having lighting that was still provided --> OK
(E) less than one percent of homes had electricity, where lighting had still been provided --> WRONG
We can eliminate options B, C, & E because they use the wrong verb formats or don't use parallel structure. Now that we have it narrowed down to only 2 options, let's take a closer look at each option with the non-underlined part attached and look for problems:
(A) 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.
This is CORRECT! By starting the modifier with the word "where," it modifies the noun directly before it, which is homes. This makes perfect sense! It also uses the proper verb tenses throughout to indicate the correct order of events.
(D) 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 there was less than 1 percent of homes that had electricity, having lighting that was still provided mainly by candles or gas.
This is INCORRECT because it includes an -ing modifier that's being used incorrectly. The -ing modifier must modify the main subject and verb of the previous clause, and in this case it's trying to modify the phrase "there was." It SHOULD modify the word "homes," but it would need to be reworded into a different type of modifier for that to work.
There you have it - option A was correct all along!
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