Scientists are convinced_____the positive effect of laughter_____physical and mental health.     
#28733
A
of; at
B
by; in
C
of; on
D
on;at
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The job is great ________salary. It has its disadvantages,though.
#25877
A
in case of
B
as a result of
C
in terms of
D
except for
_____ the rain, the football game will not be cancelled.
#26688
A
In spite of
B
In favor of
C
In need of
D
In memory of