thE ExpErimEnt ConDuCtED By thE rEsEArChEr wAs mEAnt to ______.
A．rEviEw thE DECisions oF rEFErEEs At thE 1998 worlD Cup
B．AnAlysE thE CAusEs oF Errors mADE By FootBAll rEFErEEs
C．sEt A stAnDArD oF FootBAll rEFErEEing
D．rEExAminE thE rulEs For FootBAll rEFErEEing