Bunuel wrote:
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
(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)