The study leaves some questions unanswered，however．Ms．Stash says it is not possible to say whether the amount or kind of activity affected the level of academic improvement．This is because of differences among the studies .

　　Also．they were mostly observational studies．An observational study is where researchers do not do controlled comparisons．They only describe what they observe．So they might observe a link that students who are more active often have better grades．But that does not necessarily mean being active was the cause of those higher grades．

　　The researchers said they found only two high - quality studies．They called for more high-

　　quality studies to confirm their findings．They also pointed out that “outcomes for other parts of the world may be quite different. ”

　　Still，the general finding was that physically active kids are more likely to do better in school．Ms．Singh says schools should consider that finding before they cut physical education programs．Her paper on “Physical Activity and Performance at School”is published in the Archives of Pediatric and Adolescent Medicine．

　　72．The passage mainly tells us that ＿＿＿＿

　　A．a research on physical education has been done by the researchers

　　B．there exists a possibility that physical activity leads to higher grades

　　C．the amount or kind of activity directly affects academic level

【2016年重庆渝中区高考英语阅读理解一轮选练（1）及答案】相关文章：

★ 2017届高考英语二轮复习课时训练：2（含解析）

★ 浙江省湖州市2014高考英语完形填空一轮（暑假）精炼（4）含答案

★ 2017高考四川省广安市英语阅读理解一轮系列训练：4（含解析）

★ 重庆市2014高考英语阅读理解一轮（精品）训练题（22）附答案

★ 贵州省贵阳市2014高考英语（新人教版）一轮阅读训练（26）附答案

★ 安徽省淮南市2014高考英语一轮单项选择及文章训练（9）及答案

★ 辽宁省辽阳市2014高考英语单项选择一轮（暑假）训练（8）附答案

★ 常熟市2014高考英阅读理解语一轮（暑假）训练题（12）及答案

★ 2017高考四川省广安市英语阅读理解一轮系列训练：2（含解析）

★ 四川省广安市2014高考英语一轮基础训练题（10）及答案