虚心请教一题

zkbeckham

The list of animals that exhibits a preference of either using the right or the left hand (i.e., claw,

paw, or foot) has been expanded to include the lower vertebrates.

(A) exhibits a preference of either using the right or the left hand (i.e., claw, paw, or foot) has

been expanded to include

(B) exhibits the preference to use either the right or the left hand (i.e., claw, paw, or foot) has

been expanded and includes

(C) exhibit a preference in either using the right or the left hand (i.e., claw, paw, or foot) has

been expanded to include

(D) exhibit a preference for using either the right or the left hand (i.e., claw, paw, or foot) has

been expanded to include

(E) exhibit the preference as to either using the right or the left hand (i.e., claw, paw, or foot) has

been expanded and includes
就一个问题 the list of animals that exhibits.  the list of animals 做主语 后面是has been  说明是个单数名词，为什么答案是d，exhibit没有s？
单数名词的谓语动词应该是 复数形式啊 。谢谢了

12604698

that exhibit xx 是修饰animals的定语从句