OG10 ---128 关于正确选项的疑惑！（讨论帖中没找到想要的答案，请大家帮帮忙）

GraceZhou

128. New hardy varieties of rice show promise of producing high yields without the costly requirements of irrigation and application of commercial fertilizer by earlier high-yielding varieties.
(A)    requirements of irrigation and application of commercial fertilizer by earlier high-yielding varieties
(B)    requirements by earlier high-yielding varieties of application of commercial fertilizer and irrigation
(C)    requirements for application of commercial fertilizer and irrigation of earlier high-yielding varieties
(D)    application of commercial fertilizer and irrigation that was required by earlier high-yielding varieties
(E)    irrigation and application of commercial fertilizer thatwere required by earlier high-yielding varieties

由that后的系动词were知，that指代的是irrigation and application of commercial fertilizer，我的疑惑是，that可以这样指代吗？同时指代这两个名词：irrigation and application

GraceZhou

自己顶下，也许这个问题很幼稚吧，那么多讨论帖中都没有人问
这个问题