The numbers of internet users has grown by more than a ten percent

IMO the answer should be D. We can arrive at this answer through the process of elimination:

1. "The number...has grown by", vs "The number...have grown by" - Since number is singular, it should accompany a singular verb, therefore, any option which has "have grown" can be eliminated. This eliminates C.

2. "Greater than" vs "More than" - Greater than should be accompanied with absolute numbers. Since this sentence mentions a percentage, "more than" is preferable. This eliminates B and E.

We are now left with A and D - of the two, A is awkward and employs redundant words. "More than a ten percent increase" is awkward and has incorrect idiom usage, whereas D conveys the same message and it is clear and unambiguous.

Best answer is (D)

(A) The verb "has" agrees with the plural subject "The numbers of." On the other hand, saying "more than a ten percent increase" is redundant and awkward phrasing.
(B) The number of internet users has grown by greater than ten percent in the past year.
The phrase "greater than ten percent" is not as clear as "more than ten percent." The comparative form of "greater" is usually used when comparing two things.
(C) The numbers of internet users have grown by more than ten percent in the past year.
The numbers of here in unidiomatic. Because the « numbers » in this sentence indicates « users. » You can use the numbers of when you refer to two things.
(D) This option correctly uses "the number" as the subject and the verb "has." The comparison and tense are also correct.
(E) The number of internet users grew by greater than ten percent in the past year.
This option uses the past tense "grew" instead of the present perfect tense "has grown." While both tenses can be correct depending on the context, using the present perfect tense may be more appropriate in this case, as it emphasizes the ongoing growth up to the present moment.

Considering all these factors, options (D) is the most suitable.

KAPLAN OFFICIAL EXPLANATION:

First of all, numbers in the original sentence should be changed to the singular number. The only time that the plural numbers should be used is when one wants to discuss actual numbers, as in the numbers 4 and 12. Eliminate (A) and (C). Your remaining options ask you to choose between greater than ten percent and more than ten percent. As we said earlier, greater than is correct only when it is used to describe numbers alone (greater than ten). Since this sentence measures a percent rather than solely a number, the correct option is more than. Only (D) remains.

An 800 test taker is careful when dealing with percents. While ten is clearly a countable quantity, ten percent is not and requires different terms to describe it.
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