When I try to find ______that prevent so many people from taking part in the program, it seems to me that there are two main causes.
#4996
A
why it does
B
what it does
C
what it is
D
why it is
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Obama, _______ life was once hard when he was young, were elected President of American.
#4960
A
for whom
B
who
C
to whom
D
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