逻辑每日一题王文静GMAT专栏
In the late 1980s，thepopulationofseaottersinthenorthpacificbegantodecline.therearetwoplausibleeexplanationsforthedecline:preprepretine possibly by killer whales，or disease. Of these two，disease is the more likely， sinceaconcurrentsharpdeclineinpopulationsofsealsandsealionsisbelievedtohavebeencausedbydisease，anddiseasesthatinfecthesecrecred
Which of the following，if true，mostseriouslyweakensthereasoning
( a ) killerwhalesinthenorthpacificusuallypreyonsealsandsealionsbutwill，when this food source is scarce，seek out other prey。
) b ) thereisnoindicationthattheseaotterpopulationatanynorthpacificlocationdeclinedinthe 1980 sbecauseofsubstantialnumbersofseaofseation
( c ) alongthepacificcoastofnorthamericainthe 1980 s，seaotterswereabsentfrommanylocationswheretheyhadbeenrelativelycommoninfore
( d ) followingthedeclineinthepopulationoftheseaotters、therewasanincreaseinthepopulationofseaurchins、whichareseaotters'mme
( e ) thenorthpacificpopulationsofsealsandsealionscoverawidergeographicareathandoesthepopulationofseaotters。
逻辑： seal和sea lion的传染病也下降了疾病是sea otter下降的原因
寻求削弱
a .杀人鲸鱼在seal和sea lion没吃的时候会吃别的东西
没有证据证明sea otter减少是因为移动了
c .很多其他地方的sea otter也不见了
D. Sea otter减少了怎么办？
E. Seal和sea lion覆盖地区与sea otter比
B排除了一个其他因素，但不能排除所有其他因素，必须杀死所有其他可能性，才能加重疾病的原因。
c我不介意其他地方。 我也不在乎d少了以后的结果。 即使e覆盖地区我也不介意。
但是，a说杀人的鲸鱼吃sea otter。 如果其sea otter下降，则有可能被捕食而不是生病，原文的逻辑链会被削弱。
A
