prep-1-123 they are到底省不省？？

123.       (30997-!-item-!-188;#058&004357)

According to two teams of paleontologists, recent fossil discoveries in Pakistan show that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--than to any other mammals.

(A) that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--than

(B) that whales, porpoises, and dolphins are more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--as

(C) whales, porpoises, and dolphins to be more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--than they are

(D) whales, porpoises, and dolphins as being more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today includes cows, camels, pigs, and hippos--as they are

(E) whales, porpoises, and dolphins as more closely related to some of the oldest known even-toed ungulates--a group of hoofed mammals that today include cows, camels, pigs, and hippos--than

(B) more…as… 搭配错误，应该是more… than…。

(C) 宾语从句缺少引导词that； show sth to be… 变宾语从句为名词+修饰词结构错误；they are在这种没有歧义存在的情况下可以省略，使句子更简洁。

(D) 宾语从句缺少引导词that；more…as… 搭配错误，应该是more… than…；show sth as being… 表达方式错误；they are在这种没有歧义存在的情况下可以省略，使句子更简洁。

(E) 宾语从句缺少引导词that；show sth as…表达方式错误。

想问一下 是因为画线部分后的to消除了歧异吗??

谢谢各位NN~

to some of the oldest known even-toed ungulates和to any other mammals的比较。

所以没必要补出相同的东西...

如果不考虑歧义的部分，从对称的角度来看也是应该选A。

related to ... than to.. + 宾语后that不可省略 直接就指向A了，还要考虑歧义吗？