单选题 One of the {{U}}responsibilities{{/U}} of the Coast Guard is to make sure that all ships strictly follow traffic rules in busy harbors.
  • A. cautiously
  • B. dutifully
  • C. faithfully
  • D. skillfully
【正确答案】 B
【答案解析】[解析] dutifully“守本分地”。cautiously“小心谨慎地”；faithfully“忠诚地”；skillfully“熟练地”。