Growth requires free space, and if you want to grow faster, you must give him freedom of movement instead of being stuck in a small fish tank. This phenomenon of giving more space to bring about faster development Known as the "fish tank rule". According to the above definition, which of the following phenomena belong to the "fish tank rule"? ['In order to improve his overall quality, a student has taken courses in other majors in addition to this major.', 'Promote young cadres with outstanding working abilities to important positions in a timely manner and make them assume important responsibilities.', 'Some parents do everything possible to keep their children by their side in order to give their children a stable life and work.', 'Broaden the selection of Xianmen in a western city and recruit various talents in economically developed coastal areas.']