单选题 It happened that I went out that day. The italicized part is ______.
A. the object B. an adverbial C. a predicative D. the subject

【正确答案】 D
【答案解析】[解析] 句子成分题。在题干句子中，it为形式主语，句子真正的主语是主语从句I went out that day，故D.为正确答案。A“宾语”、B“状语”以及C“表语”均不符合题意，故排除。