Country X is set to pass a national law requiring all households to

Question

Country X is set to pass a national law requiring all households to use compact fluorescent light bulbs instead of traditional incandescent bulbs. Compact fluorescent bulbs consume a small fraction of the power that incandescent bulbs use to generate the same amount of light. Home lighting makes up a significant percentage of Country X’s electrical power use. Successful enforcement of this new law will produce a substantial decrease in the country’s electricity consumption.

Which of the following would it be most useful to determine in evaluating this argument?

A. Whether Country X could generate its electricity with greater efficiency
B. Whether there is an alternative to incandescent bulbs that is more efficient than compact fluorescent bulbs
C. How extensively compact fluorescent bulbs are already used in Country X
D. The difference in price between compact fluorescent bulbs and incandescent bulbs
E. Whether requiring greater efficiency for motor vehicles would save more energy than requiring the use of compact fluorescent bulbs for lighting

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Official Answer

C

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Abhishek009 · Answer

(A) Generation of electricity is of no use, we are interested in electricity consumption.
(B)  Alternative not under discussion and out of scope.
(C) Can be true, if 90% already use then the law will have minimum effect.
(D) Difference in price not relevant to substantial decrease in the country’s electricity consumption.
(E) greater efficiency for motor vehicles - Out of scope...

Hence, IMHO (C)

Ankit__7182 · Answer

Between C and D
C. How extensively compact fluorescent bulbs are already used in Country X
YES, it will be most useful to determine in evaluating this argument. If this is already high (close to 100%), then successful enforcement of this new law will NOT produce a substantial decrease in the country’s electricity consumption.

D. The difference in price between compact fluorescent bulbs and incandescent bulbs.
Price is irrelevant here because this national law requires all households to use compact fluorescent light bulbs. (even if cost is high).

PG695 · Answer

Notice the last sentence of the passage:

The author concluded that "successful enforcement will lead to a   SIGNIFICANT REDUCTION   in electricity consumption." So, what do we need to evaluate here? Obviously, it's whether this plan/strategy will achieve its goal (significant reduction in electricity consumption) or not.

Looking at the choices we have, C asks: How extensively this .... bulbs are already used in Country X.
This question (choice) is most helpful to determine IF IT WILL BE A SIGNIFICANT REDUCTION or not because:

YES (Very extensive usage)  -> the significant reduction  WILL NOT  occur

NO (Not extensive usage)  -> the significant reduction  WILL  occur

Dream009 · Answer

Which of the following would it be most useful to determine in evaluating this argument? 
  My thinking to mark this in 1.5 mins

A. Whether Country X could generate its electricity with greater efficiency -  Don't care about production but consumption
 B. Whether there is an alternative to incandescent bulbs that is more efficient than compact fluorescent bulbs -  Out of scope of passage
 C. How extensively compact fluorescent bulbs are already used in Country X -  No reason to eliminate Keep  
 D. The difference in price between compact fluorescent bulbs and incandescent bulbs -  Price is not a part of premise - how can we evaluate with this
 E. Whether requiring greater efficiency for motor vehicles would save more energy than requiring the use of compact fluorescent bulbs for lighting -  This is again like B giving us an alternative. And comparison has to happen b/w traditional bulbs and new bulbs + scope is only motor vehicles - eliminate

Answer is what we could not eliminate

Country X is set to pass a national law requiring all households to

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Country X is set to pass a national law requiring all households to