I'm anxious about what note he took in the back of his diary ______ things to mend or replace.
A.ofB.inC.withD.by在线课程A
解析：
句意：我对于他日记中为了修补或替换某些东西所做的记录感到很担心。take note of为固定短语，意为“做笔记，注意（到），留意（到）”，又如：The committee has taken note of objections.该委员会已注意到反对意见。students taking notes in a lecture听课时做笔记的学生。