Unidentified Flying Object Unidentified Flying Object (UFO) is any object or light, reportedly sighted in the sky, that cannot be immediately explained by the observer. Sightings of unusual flying objects date back to ancient times, but UFOs (sometimes called flying saucers) became widely discussed only after the first widely publicized U. S sighting in 1947. Many thousands of such observations have since been reported worldwide. At least 90 percent of UFO sightings can be identified as conventional objects, although time—consuming investigations are often necessary for such identification. The objects most often mistaken for UFOs are bright planets and stars, aircraft, birds, balloons, kites, aorial flares, peculiar clouds, meteors, and satellites. The remaining sightings most likely can be attributed to other mistaken sightings or to inaccurate reporting, tricks, or delusions, although to disprove all claims made about UFOs is impossible. From 1947 to 1969 the U. S. Force investigated UFOs as a possible threat to national security. A total of 12,618 reports were received, of which 701 reports, or 5.6 percent, were listed as unexplained. The air force concluded that "no UFO reported, investigated, and evaluated by the Air Force has ever given any indication of threat to our national security". Since 1969 no agency of the U.S. government has had any active program of UFO investigation. Some persons, however, believe that UFOs are extraterrestrial spacecraft, even though no scientifically valid evidence supports that belief. The possibility of extraterrestrial civilizations is not the stumbling block; most scientists grant that intelligent life may well exist elsewhere in the universe. A fully convincing UFO photograph has yet to be taken, however, and the scientific method requires that highly speculative explanations should not be adopted unless all of the more ordinary explanations can be ruled out. UFO enthusiasts persist, however, and some persons even claim to have been captured and taken aboard UFOs. No one has produced scientifically acceptable proof of these claims. Behavioral scientist Carl Sagan once proposed that "certain psychological needs are met by belief in superior beings from other worlds. \ According to the passage, the belief that some UFOs are spaceships from some extraterrestrial civilizations ______
A. has been supported by a convincing UFO photograph
B. would be accepted if it met the requirements of the scientific method
C. has been regarded as some kind of creative thinking
D. has ruled out other explanations about the origin of UFOs
A. can be found in ParisB. the major events of the nationC. of the country’s industriesD. a lot of cinemas and theatresE. has been growing steadilyF. has been decreasing rapidly Paris is not only the center of education of France, but also the center ______.
High Percentage of Accidents Placing a human being behind the wheel of an automobile often has the same curios effect as cutting certain fibres in the brain. The result in either case is more primitive behaviour. Hostile feelings are apt to be expressed in an aggressive way. The same man who will step aside for a stranger at a doorway will, when behind the wheel, risk an accident trying to beat another motorist through an intersection. The importance of emotional factors in automobile accidents is gaining recognition. Doctors and other scientists have concluded that the highway death toll resembles a disease epidemic and should be investigated as such. Dr Ross A. McFarland, Associate Professor of industrial Hygiene at the Harvard University School of Public Health, aid that accidents "now constitute a greater threat to the safety of large segments of the population than diseases do. " Accidents are the leading cause of death between the ages of 1 and 35. About one third of all accidental deaths and one seventh of all accidental injuries are caused by motor vehicles. Based on the present rate of vehicle registration, unless the accident rate is cut in half, one of every 10 persons in the country will be killed or injured in a traffic accident in the next 15 years. Research to find the underlying causes of accidents and to develop ways to detect drivers who are apt to cause them is being conducted at universities and medical centres. Here are some of their findings so far: A man drives as he lives. If he is often in trouble with collection agencies, the courts, and police, he will have repeated automobile accidents. Accident repeaters usually are egocentric, exhibitionistic, resentful of authority, impulsive, and lacking in social responsibility. As group, they can be classified as borderline psychopathic personalities, according to Dr. McFarland. The suspicion, however, that accident repeaters could be detected in advance by screening out persons with more hostile impulses is false. A study at the University of Colorado showed that there were just as many overly hostile persons among those who had no accidents as among those with repeated accidents. Psychologists currently are studying Denver high school pupils to test the validity of this concept. They are making psychological evaluations of the pupils to see whether subsequent driving records will bear out their thesis. According to Dr. McFarland, accident repeaters are ______
A. shy
B. borderline psychopathic cases
C. criminally insane
D. neurotic