道路沥青是由（）后的残留物经浅度氧化而得来的。
A、常压蒸馏
B、减压蒸馏
C、常减压蒸馏
D、延迟焦化
参考答案：C
The weather in Beijing is colder than ______. [ ]
A. in Hefei
B. Hefei
C. that in Hefei
D. that of Hefei
环境影响识别
