单选题 How can a single postage stamp be worth $16,8007
Any mistake made in the printing of a stamp raises its value to stamp collectors. A mistake on one inexpensive postage stamp has made the stamp worth a million and a haft times its original value.
The mistake was made more than a hundred years ago in the British colony of Mauritius, a small island in the Indian Ocean. In 1847 an order for stamps was sent to a London printer - Mauritius was to become the fourth country in the world to issue stamps.
Before the order was filled and delivered, a ball was planned at Mauritius' Government House, and stamps were needed to send out the invitations. A local printer was instructed to copy the design for the stamps. He accidentally inscribed the words "Post Office" instead of "Post Paid" on the several hundred stamps that he printed.
Today there are only twenty-six of these misprinted stamps left - fourteen One penny Orange-Reds and twelve Two-penny Blues. Be cause of the Two penny Blue's rareness and age, collectors have paid as much as $16,800 for it.

单选题 A postage stamp's value to collectors is raised if______.

【正确答案】 D

【答案解析】根据全文分析，影响邮票收藏价值的有几个因素：第一，它是否印制有错误(第一段)；第二，它的数量多少(最后一句，rareness)。第三，它的历史长短。(最后一句，age)，所以A、C都是其中之一，所以选D。

单选题 In 1847 most countries of the world were______.

【正确答案】 C

【答案解析】文中提到，In 1847 an order for stamps was sent to a London printer—Mauritius was to become the fourth country in the world to is sue stamps．说明当时发行邮票的国家比较少。

单选题 The mistake on the locally printed postage stamps was in the______.

单选题 The collectors' have paid $16,800 for______.

【正确答案】 C

【答案解析】根据最后一句，Because of the Two penny Blue's rareness and age，collectors have paid as much as $ 16，800 for it。其中的it指的只是the Two penny Blue。