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单选题
Before closing the hatch, it is mandatory to ensure that no persons are in the crew rest compartment.
A
Unless you close the hatch, ensure that persons are in the crew rest compartment.
B
Before you close the hatch, make sure that no persons are in the crew rest compartment.
C
Before you close the hatch, notice whether or not that there is persons are in the crew rest compartment.
答案解析
正确答案：B
