答案：D

题目分析：考查倒装句。句意：护士们不仅要求涨工资而且要求减少劳动时间。此处后面的but also被省略，not only引导的句子置于句首时，需部分倒装。故选D。

【知识拓展】

not only.., but also...连接并列分句且置于句首时前倒后不倒，但连接并列主语时不倒装。

Not only did the garage overcharge me, but they hadn't done a very good repair job either.

修车厂不仅对我超额收费，而且维修工作还很差。

Not only will help be given to people to find jobs, but also medical treatment will be provided for people who need it.不仅帮助人们寻找工作。而且也将提供医疗给那些需要的人。