51. What is the purpose of the new U.S. space policy?
- A. To lay out general guidelines for space exploration.
- B. To encourage companies to join in space programs.
- C. To make the best use of satellites in space.
- D. To improve traffic conditions in space.
答案：D
答案句：Officials at the White House announced a new space policy focused on managing the increasing number of satellites that companies and governments are launching into space. Space Policy Directive-3 lays out general guidelines for the United States to mitigate (缓解) the effects of space debris and track and manage traffic in space.
参考译文：白宫官员宣布了一项新的太空政策，重点是管理公司和政府发射到太空的日益增多的卫星。太空政策指令-3为美国制定了缓解太空碎片影响以及跟踪和管理太空交通的总体指导方针。
定位线索：题干“purpose of the new U.S. space policy”→答案句“a new space policy focused on managing...track and manage traffic in space”；文中“manage traffic in space”对应选项D“improve traffic conditions in space”。
解析：题干问新政策的目的，答案句明确指出政策“focused on managing the increasing number of satellites”和“track and manage traffic in space”，即管理太空交通，对应D项“improve traffic conditions in space”。A项“lay out general guidelines”是政策内容而非目的，且“space exploration”范围扩大；B项“encourage companies”无中生有；C项“make the best use of satellites”偷换概念，政策是管理而非利用。