Political opinion and analysis outside the mainstream rarely are found on television talk shows, and it might be thought that this state of affairs is a product of the political agenda of the television stations themselves. In fact, television stations are driven by the same economic forces as sellers of more tangible goods. Because they must attempt to capture the largest possible share of the television audience for their shows, they air only those shows that will appeal to large numbers of people. As a result, political opinions and analyses aired on television talk shows are typically bland and innocuous.
31. An assumption made in the explanation offered by the author of the passage is that
A.most television viewers cannot agree on which elements of a particular opinion or analysis are most disturbing.
B.there are television viewers who might refuse to watch television talk shows that they knew would be controversial and disturbing.
C.each television viewer holds some opinion that is outside the political mainstream, but those opinions are not the same for everyone.
D.there are television shows on which economic forces have an even greater impact than they do on television talk shows.
E.the television talk shows of different stations resemble one another in most respects.
B is the best answer.
先抽象原文：TV station的政治talk show是受经济利益驱使，看谁能capture the largest possible viewers，而不是TV station’s political agenda，所以，TV station的政治Talk show是bland and innocuous (柔和的和不得罪人的)。问explanation的assumption：
大部分viewer不能就opinion or analysis的哪部分最disturbing达成一致。能不能就most disturbing达成一致与收视率及bland and innocuous无关，并有一点weaken的味道。
tv reviewers拒绝看controversial and disturbing的talk show;这正好在“capture the largest possible viewers”与“bland and innocuous” 架了一座桥梁。So B is the best answer.
文章讨论的重点不是outside the political mainstream, 所以是无关项。
其他talk show 的economic forces无关。
32. The explanation offered by the author of the passage makes the assumption that
A.television station executives usually lack a political agenda of their own
B.bland and innocuous political opinions and analyses are generally in the mainstream
C.political analysts outside the mainstream are relatively indifferent to the effect their analyses have on television viewers
D.most television viewers are prepared to argue against allowing the expression of political opinions and analyses with which they disagree
E.the political opinions of television station executives are not often reflected in the television shows their stations produce
the best answer is B.
A.tv station executive is irrelevant to the explanation.
B.Yes. Because “political opinion and analysis outside the mainstream rarely found on tv talk show” , and at last the author concludes that“political opinions and analysis aired on tv talk shows are bland and innocuous”。
C.The passage doesn’t infer “political analysts outside the mainstream are relatively indifferent”, but assumes that “it might be thought…. of tv station themselves”. So C is irrelevant to the explanation.
D.This is a confusing choice. “Argue against” doesn’t indicate it will affect the tv viewers to see the talk show. It is the attitude, not the effect or result of this attitude. So it will not help the author to reason the conclusion.
E.Obviously, “the political opinion of tv station executive” is not mentioned in this passage and we can’t evaluate this situation before we get some relative information. So it is irrelevant.
Conservationist: The population of a certain wildflower is so small that the species is headed for extinction. However, this wildflower can cross-pollinate with a closely related domesticated daisy, producing viable seeds. Such cross-pollination could result in a significant population of wildflower-daisy hybrids. The daisy should therefore be introduced into the wildflower’s range, since although the hybrid would differ markedly from the wildflower, hybridization is the only means of preventing total loss of the wildflower in its range.
33. Which one of the following principles, if valid, most helps to justify the conservationist’s reasoning?
(A) It is better to take measures to preserve a valued type of organism, even if those measures are drastic, than to accept a less valuable substitute for the organism.
(B) It is better to preserve a type of organism that is in danger of extinction, even if surviving organisms of that type are not vigorous, than to allow something more vigorous to replace it.
(C) It is better to change a type of organism that would otherwise be lost, even if the changes are radical, than to lose it entirely.
(D) It is better to destroy one of two competing types of organisms, even if both are irreplaceable, than to allow both of them to be lost.
(E) It is better to protect an endangered type of organism, even if doing so has some negative effects on another type of organism, than to do nothing at all.
The best answer is C.
先理解题意：wildflower会很快extinct如果不采取措施的话。但这个wildflower能与另外一种植物daisy cross-pollinate (异花受粉)，从而produce viable seeds，产生一种杂交品种wildflower-daisy hybrid。虽然杂交后的植物differ markedly,但这是唯一一种阻止wildflower在其领域消失的方式。提问哪种原则能支持这种推理?
原文是cross-pollinate and produce seeds, 而不是preserve。
“change a type” 与“produce seeds”、“wildflower-daisy hybrids”相符;“radical”与“markedly”相对应。 So C is the best answer.
negative effects 无关，排除
34. Which one of the following is an assumption on which the conservationist’s reasoning depends?
A.The wildflower currently reproduces only by forming seeds.
B.The domesticated daisy was bred from wild plants that once grew in the wildflower’s range.
C.Increasing the population of the wildflower will also expand its range.
D.Wildflower-daisy hybrids will be able to reproduce.
E.The domesticated daisy will cross-pollinate with any daisy like plant.
B.就算daisy不是in wildflower's range，wildflower-daisy hybrids也是in wildflower's range。
D.把选项取非，变成：wildflower-daisy hybrids不能再繁殖。这样的话，总有一天，随着wildflower的消失，wildflower-daisy hybrids也会消失的，这样就不能达到prevent total loss of the wildflower in its range的目的了，从而也对结论进行了削弱。因此D为答案。
D is the best answer. 原文说“hybridization is the only means of preventing total loss of the wildflower in its range”, 如果hybrids不能reproduce，那wildflower还是会extinct。其他可在选项中加“not”看是否有影响结论。
35. Because of increases in the price of oil and because of government policies promoting energy conservation, the use of oil to heat homes fell by 40 percent from 1970 to the present, and many homeowners switched to natural gas for heating. Because switching to natural gas involved investing in equipment, a significant switch back to oil in the near future is unlikely.
The prediction that ends the passage would be most seriously called into question if it were true that in the last few years.
A.the price of natural gas to heat homes has remained constant, while the cost of equipment to heat homes with natural gas has fallen sharply.
B.the price of home heating oil has remained constant, while the cost of equipment to heat home with natural gas has risen sharply.
C.the cost of equipment to heat homes with natural gas has fallen sharply, while the price of home heating oil has fallen to 1970 levels.
D.the cost of equipment to heat homes with oil has fallen sharply, while the price of heating with oil has fallen below the price of heating with natural gas
E.the use of oil to heat homes has continued to decline, while the price of heating oil has fallen to 1970 levels
D.有oil与gas的price的比较gas equipment的过去与现在的比较，说明了用oil比用gas便宜，而且也提到了oil equipment的造价急剧下降，所以用oil会比用gas好，因此switch back to oil是合算的，是likely的，对文章起到weaken的作用。