Scientists at the Los Alamos National Laboratory have

Question

Scientists at the Los Alamos National Laboratory have suceeded for the first time in mining heat from the Earth's interior  and producing energy on a commercial scale, enough for efficient generation of electricity and heating  factories and homes.

(A) and producing energy on a commercial scale, enough for efficient generation of electricity and heating
(B) and producing enough energy on a commercial scale for electricity to be generated efficiently and to heat
(C) for energy production on a commercial scale, enough for generating electricity efficiently and to heat
(D) to produce energy on a commercial scale, enough for generating electricity efficiently and for heating
(E) to produce enough energy on a commercial scale for efficient generation of electricity and heat

shoonya · Answer

Don't you think that "enough for efficient generation of electricity and heating" means efficient generation of both electricity and heating? I think they are mining heat to generate electricity, so A and B are out. C is awkward and E has the same problem as A does. So my answer is D.

soccerfan · Answer

I'll go with Shoonya's logic. Mining heat from the Earth's interior leads to producing energy . 
Hence .. 'D'

paddyboy · Answer

A it is... They are mining heat to generate energy. From this energy they produce electricity and heat... at least thats what I thought

Futuristic · Answer

I'll go with D. First off, we're trying to mine heat to/for producing energy. Mining heat is not something that we're doing along with producing energy. This, IMO makes A and B incorrect.

C: "for generating electricity" does not agree in tense with "to heat"
E: "for efficient generation of electricity and heat factories and homes" sounds incorrect

GMATT73 · Answer

Read the entire sentence and you will soon discover that A really doesn`t make much sense. As if the scientists were successful in BOTH mining heat from the earth AND producing energy.

Also, note that A is stated in the passive voice: ---> enough for efficient  generation of  electricity and heating 

"to" in (D) clearly shows the purpose (or application) of why the mining was successful: ---> to produce energy on a commercial scale

1:46

jaynayak · Answer

Will go with A.
For ||ism and also other options change the meaning a bit

b14kumar · Answer

Good question.

It's D.

- We need "to" to show the purpose.
- "for generating" and "for heating" are ||.

In A, we are lacking "to".
Moreover, "for efficient generation" and "heating" are not ||.

Regards,
Brajesh

buzzgaurav · Answer

Picking D.
One reason being the explainations above that scientists are mining heat to produce energy.
Also ,D seems more ||.

Scientists at the Los Alamos National Laboratory have suceeded for the first time in  mining heat  from the Earth's interior  to produce  energy on a commercial scale, enough  for generating  electricity efficiently and  for heating  factories and homes.

ywilfred · Answer

'and' is out --> the underlined portion is an effect of mining heat from the Earth's interior and not part of it. (A,B out)

C - lacks parallelism
E - 'and heat' changes the meaning of the sentence

D is best.

likar · Answer

The OA is  (D) . It's great that so many people got this one right!

Btw. This is probably one of the hardest SCs you will get in GMATPrep. I got it as the last SC in the test and my final verbal score was 49, so I guess it can't get much harder than this.

GMATT73 · Answer

Wow, a V49 score is off the charts! :yikes

likar · Answer

Well, it was a 2nd retake of GMATPrep CAT1, so the score is not that much representative :-D

. Basically, all CRs were repeated (so I spared some time), but I haven't seen 90% of SCs before this test (apparently GMATPrep has a huge database of SCs) and also most passages were new to me.

mailtheguru · Answer

However, "enough for efficient generation of electricity and heating" is a modifier. should it not be close to the noun, that is 'energy'?

Scientists at the Los Alamos National Laboratory have

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards