GWD5-Q21

chenwenqian123

InTeruvia, the quantity of rice produced per year is currently just large enoughto satisfy domestic demand.  Teruvia’stotal rice acreage will not be expanded in the foreseeable future, nor willrice yields per acre increase appreciably. Teruvia’s population, however, will be increasing significantly foryears to come.  Clearly, therefore,Teruvia will soon have to begin importing rice.

Whichof the following is an assumption on which the argument depends?
A.   No pronounced trend of decreasing per capitademand for rice is imminent in Teruvia.
B.   Not all of the acreage in Teruvia currentlyplanted with rice is well suited to the cultivation of rice.
C.   None of the strains of rice grown in Teruviaare exceptionally high-yielding.
D.   There are no populated regions in Teruvia inwhich the population will not increase.
E.    There are no major crops other than rice forwhich domestic production and domestic demand are currently in balance inTeruvia.
请教各位童鞋，为什么不选E呢？？

sdcar2010

Because E is not necessary.

If you negate E), you have:
There are major crops other than rice forwhich domestic production and domestic demand are currently in balance inTeruvia.  If so, would the conclusion still hold? What if people suddenly do not like to eat those major crop other than rice? Then T still has to import rice.  The the conclusion still holdes! Thus, E) is not necessary.

Even if there are no major crops other than rice for which domestic production and domestic demand are currently in balance inTeruvia, Teruvia might not need to import rice, if, for example, there is one major crop, say corn, which is currently produced much more that what is demaned in T and which will become more popular among the consumers. Then, T will not need to import more rice.  So E) is not sufficient for the conclusion to hold.

典座

sdcar2010 发表于 2012-5-19 09:14
Because E is not necessary. If you negate E), you have:There are major crops other than rice forwhic ...

同意！