Read the following passage carefully and choose the right answers.A recent investigation by scientists of the US Geological Survey shows that strange animal behavior might help to predict future earthquakes. Investigators found such occurrences in a ten-kilometer radius of the epicenter of a fairly recent quake. Some birds screeched and flew about wildly; dogs yelped and ran around uncontrollably.Scientists believe that animals can perceive these environmental changes as early as several days before the mishap.In 1976 after observing animal behavior, the Chinese were able to predict a devastating quake. Although hundreds of thousands of people were killed, the government was able to evacuate millions of other people and thus keep the death toll at a lower level.Which one of the followings is not true?