试题要求：
The study followed the students for a decade.
试题解析：
答案：A
解析：
第二段第一句“The study followed 86 male and 98 female middle school students for a 10-year period.”表现这项研究持续了10年，选A。
考点：阅读判断,2016.10
The study followed the students for a decade.
第二段第一句“The study followed 86 male and 98 female middle school students for a 10-year period.”表现这项研究持续了10年，选A。