A recent study conducted by the Pine Street Foundation showed that a dog’s nose may have the ability to detect cancer. A dog’s nose, which was the “medical device” used as part of the research, is believed to be among the world’s most powerful olfactory(嗅觉的) sensors. The study was conducted with 169 subjects 55 of which had been diagnosed as having lung cancer, 31 have breast cancer and 83 control subjects——people without cancer. During the study, five professionally trained scent dogs were used to distinguish between the breath samples of cancer patients and those who were healthy. With an average of 90% accuracy, the research was deemed a success. The Pine Street Foundation conducted its research on the belief that cancer cells give off a different type of metabolic(新陈代谢) waste product than normal cells. According to the study, the difference is so great that it can be detected by a dog’s sense of smell, including both early and late stages of the disease. In the conclusion of the study the Pine Street Foundation said that even ordinary dogs may be trained to identify the presence of cancer with only a breath sample. The organization also said that dogs can recognize the disease with astonishing amount accuracy and, finally, that the dog’s detection was not hindered(妨碍) by the presence of age, smoking or stage of cancer. The Pine Street Foundation plans to continue their research and is currently seeking funding to launch new studies. 小题1:If we want to add several different detecting examples to the passage, we should write them __________. A．between paragraph 1 and paragraph 2 B．between paragraph 2 and paragraph 3 C．between paragraph 3 and paragraph 4 D．before paragraph 1 or after paragraph 4 小题2:The best title for this passage might be ______. A．Dogs may smell cancer B．Why dogs can smell cancer C．A Study on dogs’ special ability D．A study on breast cancer 小题3:Dogs can smell cancer because ____________. A．they can detect faster than man B．their sense of smell is very sensitive C．dogs metabolize the food slowly D．patients give off bad smell 小题4:People can know from the passage _________. A．all dogs can be used to smell cancer B．it’s not easy to find out cancer in the early stage C．most of the research experiments are successful D．dogs detect cancer by breathing and feeling