What did Confucius actually want to tell his disciples in the fable Catching Cicadas?

A、It’simportantforpeopletokeepmodest.;
B、Onecannotachievesuccesswithoutexpertskills.;
C、Nothingisimpossibleaslongaspeoplestrivetodotheirbest.;
D、Anundistractedmindbringsconcentrationofthespirittodothingswell.