【题目】Hangzhou marathon is a race _______aim is to help people know the importance of taking exercise.
A.where
B.whose
C.which
D.that

【答案】B
【解析】句意：杭州马拉松是旨在帮助人们了解锻炼的重要性。先行词是a race，______aim is to help people know the importance of taking exercise定语从句缺少代词，故选B项。