单选题 The defeated troops were ordered to scatter and then concentrate fifty miles to the south.
  • A. rally
  • B. attack
  • C. march
  • D. retreat


【正确答案】 A
【答案解析】concentrate意为“集中”。四个选项的意思分别是“聚集”、“攻击”、“行进”、“退却”，因此A项为正确答案。