potential energy converted into kinetic energy

[nh8404052006]

In terms of physics, the characteristic feature of the roller coaster is that the cars potential energy, gained through their being lifted by a chain drive through the Earths gravity to the top of the first drop, has been converted to kinetic energy by the time the ride ends.

A. cars potential energy, gained through their being lifted by a chain drive

B. cars' potential energy, a gain achieved as they are lifted by a chain drive

C. potential energy from the cars being lifted by a chain drive

D. potential energy of the cars, gained as a chain drive lifts them

E. potential energy gained by the cars, being achieved while a chain drive lifts them

OA:

SPOILER: D

Please explain, thank
GMAT + S12 Q23

[effective_factor]

A. cars potential energy, gained through their being lifted by a chain drive (should cars' potential energy or potential energy of car + use of being is redundant)

B. cars' potential energy, a gain achieved as they are lifted by a chain drive (they has no clear antecedent as potential energy is singular )

C. potential energy from the cars being lifted by a chain drive (potential energy of is more appropriate + being is redundant )

D. potential energy of the cars, gained as a chain drive lifts them Correct

E. potential energy gained by the cars, being achieved while a chain drive lifts them (awkward and redundant)

[adi_800]

Well..This was a easy one!!
Answer is D..
A-> being is almost always wrong on GMAT
B->Passive voice can not win over active voice. are lifted is passive. GMAT prefers Active voice over passive. they(plural) referring to singular cars potentianl energy.
C->being is almost always wrong on GMAT
D->Correct. Idea in the sentence is clearly expressed in this option.
E->being is almost always wrong on GMAT.
Please let me know if you want more details.
Aditya...

[CrazyGmatter]

D it is...