问题
选择题
The letter was______as it was the only one ever signed by the the Queen.
A．unusual
B．unique
C．rare
D．scarce
答案
答案：B
unique意思为 “独一无二的；惟一的”, 根据题干中he only one的提示, 答案为B。rare指长期缺乏而珍惜的东西；scarce指暂时缺乏从而不足的东西。Unusual指不平常的，少有的的东西，但并非独一无二。