请教一语法题

thinkers

Wher once the union had acquiesced to the prejudices of its English-speaking members y supporting the imposition of an alien tax on immigrant workers, after 1897 the United Mine Workers made a determined effort to enlist Italians and Slavs in its ranks.
谁能翻译一下这个句子，并告知它的结构？
thanks a lot

asasasas1

尽管工会曾一度对讲英语的成员所造成的伤害予以默许，即支持对移民工人征收的外国人入境税，但1897年之后煤矿工人联合会作出最终决定将意大利与斯拉夫人也列入了征税名单之中

感觉选C，首先有个转折while，接着时态had acquiesced，再有就是in support of

thinkers

(Where once the union had acquiesced to the prejudices of its English-speaking members by supporting) the imposition of an alien tax on immigrant workers, after 1897 the United Mine Workers made a determined effort to enlist Italians and Slavs in its ranks.
a)Where once the union had acquiesced to the prejudices of its English-speaking members by supporting
b)Where once the union acquiesced to its English-speaking members' prejudices for the support of
c)While once the union had acquiesced to the prejudices of its English-speaking members in support of
d)While once the union acquiesced to its English-speaking members' prejudice in supporting
e)While once the union had acquiesced to the prejudices of its English-speaking members in its supporting of

谢谢解答，还有，这句话是什么意思呢？

asasasas1

句子当中有错别字吧，最好把题目拿过来。