在分布式数据库系统中，每一个结点都是一个独立的______系统。

W: You haven’t seen a blue notebook, have you I hope I didn’t leave it in the reading room.
M: Did you check that pile of journals you’ve borrowed from the library the other day
Q: What is the man trying to say to the woman().

A. She couldn’t have left her notebook in the library.

B. She may have put her notebook amid the journals.

C. She should have made careful notes while doing reading.

D. She shouldn’t have read his notes without his knowing it.