Japan has to employ an increasing number of overseas workers because there is no easy solution to its labor .
A. decline
B. rarity
C. vacancy
D. shortage
网友回答
A. decline
B. rarity
C. vacancy
(答案→)D. shortage
解析： labour shortage 劳动力短缺。Decline 下降。rarity稀少。vacancy 空缺，未占用.