单选题 I must leave now. ______ , if you want that book I'll bring it to you tomorrow,
A. Accidentally B. Incidentally C. Occasionally D. Subsequently

【正确答案】 B
【答案解析】本题考的是副词的上下文辨析。incidentally附带的，顺便提及：根据题意，选项B为正确答案。