wE lEArn From pArAgrAph 5 thAt
A．hospitAls usuAlly rEprEsEntED By physiCiAns plAy thE DECisivE rolE.
B．thE pAyEr CAn ChECk thE. Bill givEn By thE physiCiAn/hospitAl.
C．thE pAtiEnts plAy thE DECisivE rolE.
D．thE pAyErs plAy thE DECisivE rolE.