[求助]迷糊了，什么是grammatical referent?什么是logical referent

29. In three centuries--from 1050 to 1350--several million tons of stone were quarried in France for the building of eighty cathedrals, five hundred large churches, and some tens of thousands of parish churches.

(A)  for the building of eighty cathedrals, five hundred large churches, and some

(B)  in order that they might build eighty cathedrals, five hundred large churches, and some

(C)  so as they might build eighty cathedrals, five hundred large churches, and some

(D)  so that there could be built eighty cathedrals, five hundred large churches, and

(E)   such that they could build eighty cathedrals, five hundred large churches, and

Choice A is best. The other choices are unidiomatic or unnecessarily wordy, and the pronoun they, which appears in B, C, and E, has no grammatical referent.

我那OG29举例,说B C E的they没有"grammatical referent"我认为有是several million tons of stone ,   但是我认为没有logical referent(因为they如果指代several millin tos of stone,逻辑就不通了),我理解错了吗?

我想知道造成they指代问题是,逻辑指代错误,还是语法指代错误.

请NN回答

在数量上, 要带several million tos of stone 是用 IT单数, 所以没有grammatical referent是正确的说法, 量辞都要用单数--我做这题时是理解logical flaw, 你提出来我才发现呢, 因该是这个解答吧!