[单选题]Not until very late that night ______ her house was ______ from the terrible flood.
A.did she realize, under threat
B.that she realized, under threat
C.when she realized, in decline
D.had she realized, in decline

参考答案:A

【详解】
考查倒装句和短语。句意：直到那天晚上很晚她才意识到她的房子正受到可怕洪水的威胁。not until 引起的时间状语置于句首时，句子的主谓应部分倒装 ，故排除B，C项，由时间状语until very late that night和下文的was可知，描述过去发生的事情，用一般现在时，助动词用did，under threat“受到威胁”，in decline“在衰退中，在减少”，根据句意，用under threat，故选A。