Most whales must come up for air after several minutes, _______ a few can stay under water for an hour or more.
#33567
A
while
B
or
C
for
D
so
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Father was late for work     the traffic jam, and     ,the boss blamed him for it.
#31801
A
as a result;as a result of
B
as a result of; as a result
C
as a result of;in other words
D
as a result; in other words