题干
The Canadian dollar has fallen about 20 percent in value, making that dream ski vacation in Whistler Mountains __________than ever.
A：seems more within reach
B：seem more within reach
C：seems within more reach
D：seem within more reach
答案(点此获取答案解析）
B
和
顺反两种异构形式，下列化合物中具有上述两种空间排列形式的是( )