The flywheel effect refers to the rotation of a stationary flywheel. At the beginning, you must make a lot of effort, pushing repeatedly in a circle, each cycle is very laborious, but the effort of each circle will not be wasted. The flywheel will rotate faster and faster, and after reaching a certain critical point, the gravity and impulse of the flywheel will become a part of the driving force. At this time, you don't need to exert more effort, the flywheel will still rotate quickly, and it will stop Rotation, a phenomenon similar to this is called the flywheel effect. According to the above definition, which of the following is the flywheel effect? ["An ant finds a large piece of bread, and it can't move at first; soon, another ant comes, still can't move; three, four, the fifth part . Finally, the bread was swarmed by a group of ants. Moved home.", 'In order to keep the various departments of the company always active, a company will transfer one employee from each department and add another employee every year.', 'The research team randomly selected a number of students from the list of students in a class and did not perform any tests. However, they told the school that the tests showed that these students were highly talented, but they had not yet shown. Interestingly, the final exam results of these students Indeed higher than other students.', 'A manufacturer has developed a new type of camera, and its promotional advertisements are broadcast again and again at different time periods on the TV station. When it reaches a certain level of popularity, the product finally has a wide range of routes. At this time, it only needs to broadcast advertisements during prime time. Keep sales.']