In my opinion, you can widen the of these improvements through your active participation.

网友回答

A. dimension
B. volume
C. magnitude
(答案→)D. scope
解析：scope(=the area within the limits of a questions, subject ect. ; range)(活动)范围，机会，余地：The politics of a country would be outside the scope of a book for tourists.(一个国家的政治不属于旅游手册的内容范围之内。)dimension尺寸，尺度；magnitude大小，数量；volume体积。均不切题，不能入选。
　　本题译文：依我看，通过你的积极参与，你能够扩大这些改进措施的范围。