单项选择题
A．How did stamps begin t6 be used B．Why were postmen sent to get postage C．When did people first begin to use stamps D．Who was the first to think of using stamps
A．was paid by the letter-writers B．was paid by the letter-receivers C．was got by postmen D．both B and C
A．invented the first stamp B．was a postman in England C．gave the idea to use stamps D．was the first man to use stamps