题目内容：
According to the writer of this passage, a possible reason for the disappearances is that __________.
A．the sailors and airmen were taken away by people from space for scientific research B．Some navigational instruments ran out of order and therefore caused the ships' sinking and the planes' crashing
C．the sailors and airmen could not stand the extreme weather conditions and they died natural death
D．Some sailors and airmen were inexperienced and were responsible for the accidents
参考答案：
答案解析：