ACCorDing to thE pAssAgE, thE most sEvErE proBlEm CurrEntly FACing sCiEntists in ConClusivEly DEtErmining whEthEr CErtAin DinosAurs wErE wArm-BlooDED is
A．proving thAt thErmorEgulAtion is thE primAry mEAns By whiCh mEtABoliC rAtEs ArE inFluEnCED
B．DEvEloping A wAy oF Distinguishing BEtwEEn oxygEn 18 AnD oxygEn 16
C．showing thAt An ABsEnCE oF sEAsonAl vAriAtion in oxygEn 16 impliEs A ConstAnt intErnAl tEmpErAturE
D．FinDing A sAmplE oF DinosAur tissuE whiCh hAs survivED 65 million yEArs in A rElAtivEly intACt Form
E．(E) DEtErmining whiCh spECiEs oF DinosAurs wErE most likEly to BE wArm-BlooDED, AnD FoCusing rEsEArCh thErE