新东方对AB模式和BA模式问题的回复 绿色字部分是新东方老师的回答。

做了那么久的题，对题目中哪个是B，哪个是A，仍旧不能分得很清楚。

请问下面几题中，哪些代表A， 哪些代表B？

15. The cost of producing radios in Country Q is ten percent less than the cost of producing radios in Country Y. even after transportation fees and tariff charges are added, it is still cheaper for a company to import radios from Country Q to Country Y than to produce radios in Country Y.

The statements above, if true, best support which of the following assertions?

C. the tariff on a radio imported from Country Q to Country Y is less than ten percent of the cost of manufacturing the radio in Country Y.

第一句是A,第二句是B.

请问OG 48题中的(我昨天问的题）assumption即非A ，也非B？assumption只是B的一个必要条件，和A没有关系吗？这里的A和B 之间 也没有充分关系和必要关系吧？

48. A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The researcher concluded from this experiment that the immune system protects against mental illness as well as against

physical disease.

The researcher’s conclusion depends on which of the following assumptions?

D. Mental illness does not cause people’s immune-system activity to decrease.

第一句是A,第二句是B.
conclude得出的是结论。assumption是B的必要条件，有时和A有关系，有时和A没关系。 A是前提，是我们需要承认的。

17. Toughened hiring standards have not been the primary cause of the present staffing shortage in public schools. The shortage of teachers is primarily caused by the fact that in recent years teachers have not experienced any improvements in working conditions and their salaries have not kept pace with salaries in other professions.

Which of the following, if true, would most support the claims above?

D. Many teachers have cited low pay and lack of professional freedom as reasons for their leaving the profession.

两句都是结论，都是B