求助Prep里面一道新题

Section 301 of the 1988 Omnibus Trade and Competitiveness Act enables the United States Trade Representative to single out a country as an unfair trader, begin trade negotiations with that country, and if the negotiations do not conclude by the United states govenment's being stisfied, to impose sanctions.

A) by the Unites States government's being satisfied, to impose

B) by the United States government's satisfaction, impose

C) with the United States government's being satisfied, imposing

D) to the United States government's satisfaction, impose

E) to the United States government's satisfaction, imposing

我选的是B，可是答案是D，不懂啊不懂，。。conlcude to..? 字典里也有conclude by可是没有conclude to 这么一说阿。。。

to one's satisfaction 是一个固定用法

eg.to my surprise, to my satisfaction