Researchers used ACT scores as a measure of intellectual aptitude.

研究人员用美国大学入学考试（ACT）成绩来衡量其智力资质。

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Some will argue a test is the fairest way to measure a child's natural aptitude, and perhaps this is true in later years.

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The best-known measure is, of course, the Scholastic Aptitude Test, taken by college-bound seniors only but widely used as a proxy for school performance despite its proprietor's continuous protestations that it was not designed for that purpose.

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