When an active tooth in the shark’s jaws is lost or worn down, many spare teeth lie in seemingly limitless reserve, each of which are ready to slide into the appropriate position.

1. When an active tooth in the shark’s jaws is lost or worn down, many spare teeth lie in seemingly limitless reserve, each of which are ready to slide into the appropriate position.
2. Whenever an active tooth is lost or worn down, many spare teeth lie in seemingly limitless reserve in the shark’s jaws, which are each ready to slide into the appropriate position.
3. Many spare teeth lie in seemingly limitless reserve in the shark’s jaws, each one of which are ready to slide into the appropriate position when an active tooth is lost or worn down.
4. The many spare teeth lying in seemingly limitless reserve in the shark’s jaws, each one of which is ready to slide into the appropriate position whenever an active tooth is lost or worn down.
5. In the shark’s jaws, many spare teeth lie in seemingly limitless reserve, each one ready to slide into the appropriate position whenever an active tooth is lost or worn down.

答案是A, 但是each of which 应该是用单数吧? 请大侠们指点迷津.多谢!另外,我搜索了一下,怎么都没有看到第二套GWD的讨论?

我倒觉得答案应该选C；从逻辑意思上考虑。

A肯定不对，如LZ所说，单复数都搞错了。

我也觉得从强调部分来看，应该是C。不过不太确定这个each one of which是用复数吗？

E也不对吧,each one ready也应该是用单数啊.

E里面的each one ready 原本是 each one （being) ready, 省略了being

多谢回答!可以请教一下这里为什么省略吗?偶是菜鸟...