Editorial: Contrary to popular belief, teaching preschoolers is not especially difficult, for they develop strict systems (e. g. , for sorting toys by shape), which help them to learn, and they are always intensely curious about something new in their world. Which one of the following, if true, most seriously weakens the editorial's argument? ['Children intensely curious about new things have very short attention spans.', 'Preschool teachers generally report lower levels of stress than do other teachers.', 'Preschoolers have a tendency to imitate adults, and most adults follow strict routines.', 'Some older children also develop strict systems that help them learn.']