Until a few centuries ago, any large bones discovered in the fields or caves of LACE w:st="on">EuropeLACE>, now known to be large prehistoric animals, were usually assumed to be the remains of giants and were often displayed as curiosities in castles, palaces, town halls, churches, and monasteries.

1. now known to be large prehistoric animals, were usually assumed to be
2. presently known as from large prehistoric animals, were usually assumed as
3. bones now known to be those of large prehistoric animals, were usually assumed to be
4. bones known at present as of large prehistoric animals, were usually assumed as those of
5. currently known as those of large prehistoric animals, were usually assumed to be those of

答案C中，bones now know to be those of large prehistoric animals中bones 是什么成分呢？

同位语

Any large bones, bones now known..., were usually ...

我想问问stevegt，哪儿下载ＧＷＤ１３套之后的题啊，谢了

最近两天就可以在这里下载了。