Whether the buildings in this area should be pulled down has remained ; people are still l

Whether the buildings in this area should be pulled down has remained ; people are still looking for other possible solutions.
A. unchallenged
B. relevant
C. controversial
D. contradictory

A. unchallenged(答案→)B. relevantC. controversialD. contradictory解析：A未受到挑战的；不成问题的；未引起争论的；无异议的；B有关的，中肯的；相关联的；确切的；有重大意义[作用]的；D adj.矛盾的；反驳的；抗辩的；句义：这个地区的建筑物是否要被拆毁事关重大，人们仍然在寻找其他可能的解决方法。根据句义说明本句的relevant表示有重大意义的。故B正确。

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