A、A pair of infected glasses. B、An adult who carried thallium virus. C、A harmful substance used in a pesticide. D、Machinery used

One girl became seriously ill in New York. Doctors there were unable to diagnose the cause of her illness with confidence, so she was sent to Paris, where specialist help was available. She was then only semi-conscious and on the " Dangerously ill" list. A team of doctors hurried to examine the girl to discover that they, too, were baffled by the very unusual symptoms. While they were discussing the girl’ s case, a nurse asked to speak to them.
    " Excuse me," said the nurse, " but I think the girl is suffering from thallium poisoning. " "What makes you think that?" Dr. Brown asked. "Thallium poisoning is extremely rare. " "A few days ago, I was reading a novel" , the nurse explained. "In the novel, thallium poison is used and all the symptoms are described. They’ re exactly the same as the girl’ s.
    "You are very observant and you may be right. " another doctor said. "We’ 11 carry out some tests and find out whether it’ s thallium poisoning or not. "
    The tests showed that the girl indeed was suffering from the thallium poison, a rare metallic substance used in making optical glass. Once they knew the cause of illness, the doctors were able to give the girl the correct treatment. She soon recovered and was back to New York. Enquires revealed that the poison might have come from an insecticide used in New York.
26. Who first suggested the right cause of the case?
27. Why was the girl sent to Paris?
28. What caused the girl’ s illness?
29. What attitude of the doctors when the nurse proposed her idea?
30. What did the doctors think of the girl’ s illness when she was first admitted to hospital in Paris?