求指导：两个选项什么区别

mattam

阅读大全51篇第四题：
(A) At three different companies, approximately nine out of ten of the workers were eligible to buy shares in their companies.
(B) Approximately 90% of the eligible workers at three different companies chose o buy shares in their companies.

我选A,答案B,不明白。。。。求指导！感激涕零！！！

mattam

呜呜呜。。。。怎么办