单选题 All human beings have a comfortable zone regulating the ______ they keep from someone they talk with.
      A) distance            B) scope             C) range             D) boundary
【正确答案】 A
【答案解析】人们谈话的时候，保持彼此的距离可以使人感到舒适。
   在keep…from结构中只有distance可搭配。