Unlike the speed with which the Silver Queen corn must be rushed to ma

Wrong comparison in A. BCD corrected that error.

only C is correct grammatically and meaning wise too.

Unlike ____ , comparison

in a the speed is compared to the corn incorrect
similar error in E

a and e eliminated

b,c,d

,which modifies the closest noun and C is grammatically correct

(C) imo

Unlike the speed with which the Silver Queen corn must be rushed to market soon after picking in order to preserve its sweetness, newly bred hardier varieties can retain their sweetness for 48 hours or more under refrigeration.

A) the speed with which the Silver Queen corn must be rushed to market soon after picking in order to preserve its sweetness....... Incorrect Comparison
B) Silver Queen corn, having to be rushed to market soon after it is picked to preserve its sweetness,.....having modifying the preceding clause which is incorrect. Need to modify the Silver Queen corn
C) Silver Queen corn, which must be rushed to market soon after picking in order to preserve its sweetness,.Correct
D) Silver Queen corn, which, by rushing to market soon after picking, can preserve its sweetness,...wrong meaning
E) the sweetness of Silver Queen, which can be preserved only by rushing it to market soon after picking.......... Incorrect Comparison

This sentence deals with a comparison. The comparison is between 'Newly Bred harder varieties' and 'Silver Queen corn'. So eliminate the options A (speed is compared) and E (the sweetness is compared).

Among B, C and D:
D) - Illogically implies that the SQ corn is rushing to the market soon after it has been picked.
B)- Having to be rushed soon after it is picked- must modify a clause- (Giving details about the action/result) Hence it cannot modify the clause newly bred harder varieties.
C) is the correct answer- as the modifier logically describes the speed with which it is rushed to the market.

Here we are comparing “Silver queen corn” and “newly bred varities”. So, “Silver queen corn” should follow “unlike”. Hence, Choice A and E are out. B is incorrect because we want a simple noun modifier. "Having" modifies an entire independent clause but whats before it is not an independent clause while D is incorrect because if you look at the modifier and eliminate the fluff, it is "which can preserve its sweetness" and that doesn't properly modify Silver Queen Corn. C makes the correct comparison and uses the correct modifier. Hence, C is the answer.

chetan2u, this one is asked in Official Mock. Could you please tag it under GMAT Prep?

___________________________
Added the tag. Thank you!

A) the speed with which the Silver Queen corn must be rushed to market soon after picking in order to preserve its sweetness,

Explanation: Illogical comparison between ‘the speed with which…’ and ‘Newly bred varieties’. Also, Unlike must always be followed by noun.

B) Silver Queen corn, having to be rushed to market soon after it is picked to preserve its sweetness,

Explanation: The past tense of the sentence makes the sentence illogical. It is fact and must be presented in present tense. "Having" modifies an entire independent clause but whats before it is not an independent clause. It is a dependent clause “Unlike Silver Queen Corn”. “Having to be rushed soon after it is picked” - must modify a clause- (Giving details about the action/result)

C) Silver Queen corn, which must be rushed to market soon after picking in order to preserve its sweetness, (Correct Answer)

Explanation: ‘Which’ correctly refers to Silver Queen Corn. Which should refer to the noun preceding it before the ‘, + Which’ structure

D) Silver Queen corn, which, by rushing to market soon after picking, can preserve its sweetness,
Explanation: ‘Which’ correctly refers to Silver Queen Corn; however, the usage of commas in the sentence can make some parts of the sentence as a non-essential modifier. Therefore, the sentence is awkward and inconsistent,


E) the sweetness of Silver Queen, which can be preserved only by rushing it to market soon after picking,

Explanation: Illogical comparison between ‘the sweetness of Silver Queen…’ and ‘Newly bred varieties’. Also, Corn is not used here which makes the sentence illogical, since the subject is ‘Silver Queen Corn’ and not the ‘Silver Queen’.

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.