A、The design of stamps. B、The color of stamps. C、The words on many stamps. D、The size of the stamps. C细节题。答案是对原文He accidentally

Millions of people in the world like collecting stamps. Any mistake made in the printing of a stamp will raise its value to stamp collectors. A mistake on one inexpensive postage stamp has also made the stamp worth a million and a half times its original value.
    One such mistake was made more than a hundred years ago in the British colony of Mauritius, a small is land in the Indian Ocean. In 1847, an order for stamps was sent to a London printer. At that time,. 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. Because of the Two Penny Blue’s rareness and age, it has been so expensive that collectors have paid as much as $16,800 for it.