—Oxfam trailwalkers in Hong Kong have to climb twenty hills and mountains.
—It’s really a tough hike.
A. through
B. around
C. over
D. along
网友回答
A. through
B. around
(答案→)C. over
D. along
解析：介词辨析. Through通过;around 在……周围；over超过，越过；along 沿着。句意：香港乐施会的毅行者必须翻越20座山。climb over 固定短语，表示“翻越”。故选C。