Despite that they were able to calculate faster than ever

+1 for E.

An easy question.

Crick

+1 E

"it" doesn't have antecedent.
E is more concise.

This question showed up as a Kaplan question of the day. The OA is E and the explanation given by Kaplan is as follows:

This question presents problems of idiom. "Despite that" in (A) is unidiomatic, and "than ever before possible" in (A), (C), and (D) is awkward. Choice (B) has a clear pronoun reference problem: the singular "it" is used to refer to the plural "computers."

In addition to the errors mentioned above, I believe there are also subject/verb disagreements within the answer choices.

Hi,

I was able to narrow down to option E. But i could not understand why "than ever before possible" is awkward . Could any one of you please help.

I eliminated options on following reasons.

A Despite that they were able to calculate faster than ever before possible -- Despite that they is wrong. Despite should be followed by possessive pronoun.
B Even though it could calculate faster than previously possible--It does not agree with the earliest computers. It is singular and the earliest computers is plural.
C Although faster in its calculating than ever before possible. -- Same as C. Its is wrong here.
D Despite their calculations being faster than ever before possible --wordy than Option E. Being is avoidable in gmat.
E Despite their unprecedented speed of calculation-- despite their is perfectly used here. Their is plural and goes well with the earliest computers. Sentence is concise.

Thanks,
Ammu

KAPLAN OFFICIAL EXPLANATION

Read the Original Sentence Carefully, Looking for Errors:
This sentence contains an idiom error. "Despite" must be followed by a noun, not the word "that." Eliminate (A).

Scan and Group the Answer Choices:

All the choices begin with connectors, and all the connectors are appropriate contrast connectors that set up the logical contrast in the original sentence between the strength and weakness of the earliest computers. The next significant difference among the choices is the pronoun: (B) and (C) use "it" or "its," while (D) and (E) use "their."

Eliminate Wrong Answer Choices:

Eliminate (B) and (C). The noun "computers" must have a plural, not singular, pronoun.

Eliminate (D). It begins correctly, but is unnecessarily longer than (E). Note that (D) uses a weak "being" construction, which is almost always wrong on GMAT Sentence Correction. Also, "faster than ever before possible" is redundant; simply faster than ever would get the job done.

(E) is the correct answer. It follows "despite" with a noun ("speed"), uses the appropriate pronoun, and is clear and concise.

TAKEAWAY: If you encounter an unfamiliar idiom, make a note of it and use it in a sentence about a person or event that is important to you. This kind of practice will help make idiomatic usage second nature.

Error Analysis:

1. "Despite that they were able to calculate faster than ever before possible" is an awkward construction.

Process of Elimination:

A. Wrong. As explained above.
B. Wrong. singular word "it" is incorrectly used to describe plural word "computers".
C. Wrong. Same error as in B. Also, "Although faster in its calculating than ever before possible" is an awkward construction.
D. "being" is incorrectly used as a modifier here.
E. Correct. This option is error free and concise.

One of the imp. rule which no one has talked about, is the usage of "THAN"
"Than" compares two nouns. In Qs. containing "than" we need to check the parallel construction.
Here in (A) Ability (-that they were able to calculate faster) is being compared to a timeline (-ever before), which in my opinion is a wrong comparison.

Besides as an add-on, it helps to replace the sentence containing "Despite" with "In spite of" and check the construction.

I put D. I really wanted E but didnt know we could use alternate words. Unprecedented wasn't in the original statement.

yupp. In fact, that's a great part about this question.