【正确答案】 D

【答案解析】[解题指导] 此题考查逻辑推理。问题是：这篇文章暗示了什么?读懂四个选项：A．All correctly printed stamps are worthless(所有正确印刷的邮票都分文不值)；B．Mauritians needed the stamps to send out invitations to a ball(毛里求斯人需要邮票寄出舞会邀请函)；C．The printer was punished for his mistake(印制商因此错误而受到惩罚)；D．Collectors are constantly looking for stamps with mistakes(收藏家们时刻都在寻觅带有瑕疵的邮票)。使用排除法，可知选项D为正确答案。