UN official is said to visit our province next month to investigate problem of housing an

UN official is said to visit our province next month to investigate problem of housing and education.
A. The; the
B. The; a
C. An; the
D. A; the

A. The; theB. The; a C. An; the (答案→)D. A; the解析：考察冠词。第一空泛指，指的是一个联合国官员，第二空特指，指的是住房和教育问题，句意为，一个联合国官员据说会在下个月来到我们省份来调查住房和教育的问题。

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