为了了解某地区初一年级7000名学生的体重情况，从中抽取500名学生的体重，就这个问题来说，下面说法中正确的是
A．样本容量是500
B．500名学生是所抽取的一个样本
C．每个学生是个体
D．7000名学生是总体
答案：A
A、样本容量是500，故本选项正确；
B、所抽取的500名学生的体重情况，是一个样本，故本选项错误；
C、每个学生的体重情况是个体，故本选项错误;
D、7000名学生的体重情况是总体，故本选项错误．
故选A．
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