The meeting was postponed,______was exactly what i wanted

The meeting was postponed,______was exactly what i wanted
A that
B which it
C and that
D this
Solomon was diligent,responsible and hardworking,________he was promoted from a clerk to a manager.
A for which
B which
C for
D that
What is ______ordered the English book?
A the lady's address in Beijing who
B the lady's address in Beijing which
C the address of the lady in Beijing who
D the address of the lady in Beijing which
This kind of solar cooker can be used only in the day time_______the sun is shining.
A when
B as
C while
D since

1.c this或that都一样,不行.which可以,是定语从句,但加了it就不行.c中用and转换主语
2.A 定语从句 句子应为：Solomon was promoted from a clerk to a manager for he was diligent,responsible and hardworking
3.c in beijing是the lady,不是address故AB错.定语从句人做先行词不用which用that
4.A in the day time 和when the sun is shining一样,作时间状语