This is the hotel _______last month.A． which they stayed B． at that they stayed C． where they s

This is the hotel _______last month.A． which they stayed B． at that they stayed C． where they s
This is the hotel _______last month.
A． which they stayed
B． at that they stayed
C． where they stayed at
D． where they stayed
The factory ______we’ll visit next week is not far from here.
A． where
B． to which
C． which
D． in which
Can you lend me the book ______the other day?
A． about which you talked
B． which you talked
C． about that you talked
D． that you talked
The engineer ______my father works is about 50 years old.
A． to whom
B． on whom
C． with which
D． with whom