A、They are two famous doctors. B、They are two well-known writers who give advice. C、They are two lawyers. D、They are two profess

Most Americans don’t like to get advice from members of their family. When they need advice, they usually don’t ask people they know. Instead, many Americans write letters to newspapers and magazines which give advice on many different subjects, including family problems, sex, and the use of language, health, cooking, child care, clothes, and how to buy a house or a car.
   Most newspapers regularly print letters from readers with problems. Along with the letter, there are answers written by people who are supposed to know how to solve such problems. Some of these writers are doctors, others are lawyers or educators. But two of the most famous writers of advice are women without special training for this kind of work. One of them answers letters addressed to "Dear Abby". The other is addressed as "Dear Ann Landers". Experience is their preparation for giving advice.
Questions 19 to 21 are based on the passage you have just heard.
19. According to the passage, from who do most Americans get advice?
20. According to the passage, why do Americans write to newspapers or magazines?
21. According to the passage, who are Abby and Ann Landers?