单选题 A survey was carried out on the death rate of new-horn babies in that region, ______ were surprising.
A. as results B. which results
C. the results of it D. the results of which

【正确答案】 D
【答案解析】[解析] which引导定语从句。句意是：在那个地区展开了新生儿死亡率的调研，其结果非常令人吃惊。根据句意推出正确答案是D选项。