20.Puritan fanatics brought to civil and military affairs a coolness of judgment and mutability of purpose that some writers have though inconsistent with their religious zeal, but which was in fact a natural outgrowth of it. (A) but which was in fact a natural outgrowth of it (B) but which were in fact a natural outgrowth of it (C) but which were in fact natural outgrowths of it (D) but it was in fact a natural outgrowth of them (E) which was in fact a natural outgrowth of it 答案：C but一般连接两个独立的句子或表转折意义的并列成分，它用在C中是什么意思呢？
再请教bluestone1GG,but which修饰 a coolness of judgment and mutability of purpose，WHICH指代a coolness of judgment and mutability of purpose，那为什么要用 were in fact natural outgrowths of it，主谓的单复数不一致了呀？
