听力原文： Robert was so good at his profession that he was able to make his living for 20 years by selling false signatures of famous Americans. Robert was born in England in 1813 and arrived in Philadelphia in 1858 to open a bookstore. At first he succeeded in selling his small but genuine collection of early U.S. autographs. Discovering his ability at copying handwriting, he began imitating signatures of George Washington and Ben Franklin and writing them on the title pages of old books. To lessen the chance of detection, he sent his imitations to England and Canada for sale and circulation. He had a hard time selling his products, because he couldn't approach a respectable buyer but must deal with people who didn't have much knowledge in the field. But Robert had many ways to make his work look real. For example, he bought old books to use aged paper of the title page, and he could treat paper and ink with chemical. In Robert's time, right after the Civil War, Britain was still fond of the southern states, so Robert invented a respectable lady known as Miss Foamy Jackson, the only daughter of General Jackson. For several years Miss Fanny's financial problems forced her to sell a great number of letters and manuscripts belonging to her famous father. Robert had to work very hard to satisfy the demand. Yet all this activity did not prevent Robert from dying in poverty, leaving sharp-eyed experts the difficult task of separating his imitations from the originals.
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A. Collecting early stamps.
B. Selling false signature.
C. Making fast food.
D. Writing detective stories.