Early this year, thousands of migrant workers cancelled their insurance due to the lack o

Early this year, thousands of migrant workers cancelled their insurance due to the lack of policy to transfer insurance between difference regions.
A. the; the
B. the; a
C. /; the
D. /; a

A. the; theB. the; aC. /; the(答案→)D. /; a解析：考察冠词。本题第一空后的名词workers是一个复数名词，而且前面有形容词migrant修饰，要单独使用，表示一类事物。第二空后的名词policy前面加a泛指一种。句意：今年早些时候，成千上万的农民工取消了他们的保险，主要是因为缺少地区间保险转换的政策。故D正确。

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