单项选择题
A．is very confused about the origin of the Earth B．might possibly reach life outside the C．believes it is possible to step off the Earth D．is historically incapable of exploring the universe
A．students should learn more up-to-date knowledge B．lack of scientific knowledge will lead to poor relations between producers and users of scientific services C．students are getting to know the importance of a good balance among the branches of knowledge D．sufficient attention should be given to bask knowledge
A．the current public school system is too complicated to be understood B．the public school system has no choice of what to teach C．it is difficult to decide whether elementary science should be taught in public schools D．the educators have to take care of both ordinary and gifted students