【阅读选择】Do you think sitting and studying all the time will improv

【阅读选择】Do you think sitting and studying all the time will improve your grades? Think again. Getting some exercise may help, too. New research with older people suggests that taking regular walks helps them pay attention better than if they didn't exercise. Walking regularly helps elderly people ______.
A、lose weight
B、become happier
C、concentrate better
D、look younger
【正确答案】：C
【题目解析】：同义词替换有题干替换、选项替换。