【题目】Not until he got seriously ill _______ the importance of health.
A.he had realized
B.he realized
C.had he realized
D.did he realize

【答案】D
【解析】考查动词时态和部分倒装。句意：直到他得了重病才会意识到健康的重要性。Not until.....，位于句首句子用部分倒装，根据句意可知句子用一般过去时态，由此可知答案为D。