1、Theinterstitial nucleus, a sub-region of the brain’s hypothalamus, is typicallysmaller for male cats than for female cats. A neurobiologist performedautopsies on male cats who died from disease X, a disease affecting no morethan .05 percent of male cats, and found that these male cats had interstitialnuclei that were as large as those generally found in female cats. Thus, thesize of the interstitial nucleus determines whether or not male cats cancontract disease X.
Which one of the following statements, iftrue, most seriously weakens the argument?
A. Nofemale cats have been known to contract disease X, which is a subtype ofdisease Y.
B. Manymale cats that contract disease X also contract disease Z, the cause of whichis unknown.
C. theinterstitial nuclei of female cats who contact disease X are larger than thoseof female cats who do not contract disease X.
D. Of1,000 autopsies on male cats that did not contract disease X, 5 revealedinterstitial nuclei larger than those of the average male cat.
E. Thehypothalamus is known not to be causally linked to disease Y, and disease X isa subtype of disease Y.
E is the best answer. Disease X is thesubtype is disease Y, if disease Y has no link with hypothalamus, X must haveno link with hypothalamus.
A, C talked about the female cat, thatcan't weaken the argument.
B talked about another disease Z, doesn'tweaken the argument.
D just shows some data, which cannot weakenthe argument.
2、 There should be a greater use of gasohol.Gasohol is a mixture of alcohol and gasoline, and has a higher octane ratingand fewer carbon monoxide emissions than straight gasoline. Burning gasoholadds no more carbon dioxide to the atmosphere than plants remove byphotosynthesis.
Each of the following, if true, strengthensthe argument above EXCEPT:
A. Cars run less well ongasoline than they do on gasohol.
B. Since lessgasoline is needed with the use of gasohol, an energy shortage is less likely.
C. Cars burn onthe average slightly more gasohol per kilometer than they do gasoline.
D. Gasohol is cheaper toproduce and hence costs less at the pump than gasoline.
E. Burninggasoline adds more carbon dioxide to the atmosphere than plants can remove.
解释：首先领会本argument的结论是：There should be a greater useof gasohol。根据提议，要选支持选项，即选出支持多使用gasohol的选项：