Studies
of the human "sleep-wake cycle" have practical relevance for matters
ranging
from
duty assignments in nuclear submarines and air-traffic
control towers
to the staff of
shifts
in 24-hour factories.
(A) to the staff of
(B) to those who staff
(C) to the staffing of
(D) and staffing
(E) and the staff of
不是关于这道题，是红色部分的and前后并列，这段话在这里读的很清楚，但是好像记得平行并列的介词in应该前后一起补出，这里可以需要不上吗？
请指点，谢谢
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