急求翻译~

傻熊有傻福

In 1994 the white house named Dr RuthR. Faden chairperson of the federal advisory committee of experts they assigned to do a report on the history and ethics of the government’s radiation experiments on humans in the 1950’s and 1960’

s .

A.they assigned to do

B.to be assigned doing

C.that was being assigned doing

D.assigned for doing

E.it assigned to do
答案是E，划线句前面的句子怎么翻译？

thechooosenone

（that） it assigned to do
。。。被it（白宫）用来做。。。

helio5

1994年，白宫任命Dr RuthR. Faden为联邦专家委员会的主席 。。。

答案是E么？
怎么那么奇怪的句子