※ 引述《Birou (十里春风不如你)》之铭言：
: Educational theorists have long hypothesized that an interest in culture and
: the arts, especially music, has a positive impact on academic performance. A
: recent study of high school seniors confirms this theory. A test measuring
: proficiency in a broad range of academic disciplines was administered to high
: school seniors in major cities in the northeastern United States. The average
: score of students who attended schools that offered classes in art history
: and music appreciation was significantly higher than that of students who
: attended schools without such cultural enrichment programs.
: The argument above assumes which of the following?
: A. At the schools offering art history and music appreciation classes,
: such classes were open to underclassmen, as well as juniors and seniors.
: B. Enrollment in the art history and music appreciation classes was
: restricted to students who had previously
: demonstrated an interest in culture and the arts.
: C. Students attending schools with cultural enrichment programs, whether
: they participated in such a program or not, possessed a higher average level
: of interest in culture and the arts than did students at other schools.
: D. Among students attending schools offering cultural enrichment classes,
: those enrolled in such classes
: performed better on the test than did those not enrolled in such classes.
: E. Students attending the schools that did not offer enrichment programs
: had no other opportunities to develop interest in culture and the arts.
: 题目意思是说，对文化和艺术有兴趣，可以提高学业成绩。最近一项研究显示，有提供艺
: 术和音乐欣赏的学校同学学业分数比没有提供这些课程的学校同学来的高。
: 我选 (E)，但答案是 (C)。看了一下之后，我觉得 (C) 是 ok 的。但为何 (E) 错呢?
正巧 2013 年有解过此题 (时间过真快)，原文章连结如下:
https://www.ptt.cc/bbs/GMAT/M.1370933991.A.1F7.html
在此改写一下自己曾经的解法
以实验结果得到推论的类型