Bunuel
Today, because of the greater efficiency of communicating online, the number of people who can participate in a given meeting is double the number that it has been in 1995.
A. double the number that it has been
B. twice as many as it was
C. as much as twice the number it was
D. two times as many people as there were
E. a doubling of the people as
Official Explanation
Creating a filter: in this question, the original sentence uses the present perfect where simple past tense is in order, because 1995 is over, as the sentence implies, and because the happenings of 1995 are not a current development. So (A) is out. We can eliminate answer choices by examining either the verb tense or the way the comparison is constructed.
Applying the filter: choice (B) might be good; it uses "as" with another "as" correctly. In (C), "as much as" is used colloquially, not precisely; it should be used to convey equivalence and for that purpose here, it's needlessly wordy. In (D), the phrase "there were" changes the meaning of the sentence; now it's talking about how many people existed, not how many people could participate in a given meeting. It's also not parallel; it should compare the number of people who can with the number of people who could. In (E), "doubling" is a gerund, the kind of word we use to form a noun only when a simple noun doesn't exist -- or, in this case, the adjective "twice."
The correct answer is (B).