The study was carried out in one small town so we can’t be sure that the results are truly

问题补充：

The study was carried out in one small town so we can’t be sure that the results are truly .

A. exact

B. proper

C. representative

D. natural

答案：

(答案→)A. exact

B. proper

C. representative

D. natural

解析：词义辨析，四个选项分别表示准确的精密的、适当的、有代表性的和自然的，根据题意选A，这项研究时在一个小镇上实行，因此我们不能确定结果是否真的准确。