My answer is (D). It took me 26 seconds.

(A) This option is eliminated because the sentence is comparing "The Earth’s inner core" to "the outer Earth", so "by" should not be there.
In addition, the passive voice is ill-advised.

(B) In this option, we cannot really figure out the grammatical part that "The Earth’s inner core, a ball of solid iron" plays.

(C) In this option, "it" must be deleted.

(E) This option can be eliminated as "slower" should be used as opposed to "more slow".
In addition, verb such as "rotate" is preferable to noun such as "rotating".

A. may be rotated slower than by the outer Earth - Not our answer (This option has a lot of errors, starting from 'rotated' which is the wrong form of the verb used in this context, 'by' should not be used here.)

B. the outer Earth may rotate more slowly than it - Not our answer (This option changes the meaning of the sentence.)

C. it may rotate slower than the outer Earth - Not our answer ('it' does not have a proper antecedent and without the sentence makes more sense.)

D. may rotate more slowly than the outer Earth - This is our answer. (None of the above errors and no complications.)

E. may be more slow at rotating than the outer Earth - Not our answer (the words 'more slow' make this option redundant.)

The OA is D.

The Earth’s inner core, a ball of solid iron, maybe rotated slower than by the outer Earth.

D. may rotate more slowly than the outer Earth

D is the correct choice. Clear and concise.

imo D.

The Earth’s inner core, a ball of solid iron, maybe rotated slower than by the outer Earth.


A. may be rotated slower than by the outer Earth

-Inner Core is compared with 'by the outer earth'- Comparison error

B. the outer Earth may rotate more slowly than it
-- Sentence structure error .. The Earth’s inner core, a ball of solid iron, is not connected well with the underlined part

C. it may rotate slower than the outer Earth
-- 'It ' is not needed ..

D. may rotate more slowly than the outer Earth
-- Comparison proper .. So correct ..

E. may be more slow at rotating than the outer Earth
-- Meaning shift error ..
Rotate is more appropriate

Ans D

A. may be rotated slower than by the outer Earth - INCORRECT
Comparison error and also usage of 'than by' is not convincing.

B. the outer Earth may rotate more slowly than it- INCORRECT
Earth's inner core,--,Outer earth - This sentence is not connected and does not give a complete sentence or meaning.

C. it may rotate slower than the outer Earth- INCORRECT
usage of pronoun 'It' is incorrect

D. may rotate more slowly than the outer Earth- CORRECT

E. may be more slow at rotating than the outer Earth- INCORRECT
'Slower' is preferred rather than 'more slow'
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IMO D

The Earth’s inner core, a ball of solid iron, maybe rotated slower than by the outer Earth.


A. may be rotated slower than by the outer Earth

B. the outer Earth may rotate more slowly than it

C. it may rotate slower than the outer Earth

D. may rotate more slowly than the outer Earth
Correct

E. may be more slow at rotating than the outer Earth

The Earth’s inner core, a ball of solid iron, maybe rotated slower than by the outer Earth.

A. may be rotated slower than by the outer Earth -> "by" is incorrect to use.

B. the outer Earth may rotate more slowly than it -> We are not continuing with "The Earth’s inner core...." to "may rotate..." Incorrect

C. it may rotate slower than the outer Earth -> We don't need "it". Incorrect.

D. may rotate more slowly than the outer Earth -> It makes sense, "slowly than the". Let's keep it.

E. may be more slow at rotating than the outer Earth -> more slow is can be said as slower. Incorrect.

So, I think D.

KAPLAN OFFICIAL SOLUTION:

Correct Choice: (D)

This sentence sounds strange and does not make complete sense. It is unclear whether a comparison is being made between the rotation speed of the Earth’s inner and outer cores OR if the inner core is being rotated BY the outer core. Either way, there is a problem here. Since the meaning of the sentence must be clarified, we must go to the answers to see what the intended meaning is. We know immediately that we can eliminate choice (A), since the sentence is unclear as written.

Choice (D) creates a clear, concise sentence whose subject and verb and makes sense.

Choice (B) creates new errors. The pronoun “it” is too far from its antecedent, “the earth’s inner core; ”the construction is awkward; and there is no verb for what sounds like the primary subject of the sentence, “The Earth’s inner core, a ball of solid iron”.

Choice (C) unnecessarily places the pronoun “it” immediately after its antecedent.

Choice (E) is wordy and awkward.
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