阅读理解A
题干:Likemanyofmygeneration,Ihaveaweaknessforheroworship.Atsomepoint,however,weallbegintoquestionourheroesandourneedforthem.Thisleadsustoask:Whatisahero?Despiteimmensedifferencesincultures,heroesaroundtheworldgenerallyshareanumberofcharacteristicsthatinstructandinspirepeople.Aherodoessomethingworthtalkingabout.Aherohasastoryofadventuretotellandacommunitywhowilllisten.Butaherogoesbeyondmerefame.Heroesservepowersorprincipleslargerthanthemselves.Likehigh-voltagetransformers,heroestaketheenergyofhigherpowersandstepitdownsothatitcanbeusedbyordinarypeople.Theherolivesalifeworthyofimitation.Thosewhoimitateagenuineheroexperiencelifewithnewdepth,enthusiasm,andmeaning.Asuretestforwould-beheroesiswhatorwhomdotheyserve?Whataretheywillingtoliveanddiefor?Iftheanswerorevidencesuggeststheyserveonlytheirownfame,theymaybefamouspersonsbutnotheroes.MadonnaandMichaelJacksonarefamous,butwhowouldclaimthattheirfansfindlifemoreabundant?Heroesarecatalysts(催化剂)forchange.Theyhaveavisionfromthemountaintop.Theyhavetheskillandthecharmtomovethemasses.Theycreatenewpossibilities.WithoutGandhi,IndiamightstillbepartoftheBritishEmpire.WithoutRosaParksandMartinLutherKing,Jr.,wemightstillhavesegregated(隔离的)buses,restaurants,andparks.Itmaybepossibleforlarge-scalechangetooccurwithoutleaderswithmagneticpersonalities,butthepaceofchangewouldbeslow,thevisionuncertain,andthecommitteemeetingsendless.
题目:Madonna and Michael Jackson are not considered heroes because_____.