The road is covered with snow. I can’t understand ________ they insist on going by motor-bike.    
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A
why
B
whether
C
when
D
how
推荐题目
The cost of sales makes up a large part of the prices that _____. 
#73486
A
are paid for all products
B
all products are paid
C
for which all products are paid
D
for all products paid