A、She cannot work in London. B、She cannot live in London. C、It is difficult for her to finish her studies. D、It’ll be difficult

Debra is a student at Oxford. A year ago, she was extremely thin, got headaches, couldn’t concentrate, and forgot things. Her face was spotty: her stomach was always upset: she couldn’t sleep. For a long time, no one could help her. Her doctor used to give her sleeping pills, but each new kind only worked for a short while. Then, after talking to a friend with similar problems, Debra began to think she might be sensitive to foods and chemicals. She went to see a specialist. The specialist tested her and found out that she was sensitive to things she ate, breathed and touched. Now, Debra is much better. She takes medicine, but she also has to avoid some of the things that make her ill. Things like fumes from cars and chemicals in food all hurt her. So she has to use a special air filter, and avoid tinned or packaged food. Fortunately she shares a house with other women who understand her problem, and they share the cooking and shopping for her diet. Debra will finish her studies this year and begin looking for a job, but she is worried that this will be difficult. Most of the jobs that interest her are in London, but she cannot live there because of the polluted air. So learning what was causing her problems has complicated her life, but she sleeps well and is healthy most of the time now.
Questions 19 to 21 are based on the passage you have just heard.
19. What was wrong with Debra a year ago?
20. What is the real reason for her illness?
21. What worries her recently?