A recent United States Census Bureau report shows that there are more than three times as many households where the children and grandchildren are living in their grandparents' home
as compared to households where the grandparents are living in their children's or grandchildren's home.
(A) as compared to households where the -- redundancy - "compared to" can NEVER be used together with another comparison word (more, less, twice, half, three times...).
(B) as there are households where the - Correct
(C) as those whose -- The word "those" is a pronoun, and needs an antecedent. The structure of this comparison dictates that the antecedent for "those" be "households"... and then you follow that pronoun with the possessive "whose". So, do the households have grandparents?
Or is the sentence merely comparing households where the living arrangements are different?
If you say "households whose", the households have grandparents. If you say "households where", then the households are merely the place in which the living arrangements exist.
(D) than compared to those where the - idiom issue - as many ... as
(E) than there are whose - idiom issue - as many ... as
Option B -->
The second "there are..." isn't strictly necessary. Without it, you'd have a sentence with the same structure as "In most countries, there are as many men as women."
Its primary value lies in making the sentence easier to read.
This is not an issue of right and wrong"”it's a style issue"”and so it will never be dispositive in a real problem. Still, you should know it's a thing.
Try writing out the entire sentence without the second "there are".
The same principle is at work behind the inclusion of many other technically unnecessary things, e.g., the use of Just as xxxxx, so yyyy rather than just "Just as xxxxx, yyyy".
Answer B
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