在CSS中,BODY{margin:10pt20pt30pt}等同于()
A.
BODY{margin-top:10pt;margin-right:20pt;margin-bottom:30pt;margin-left:0pt}
B.
BODY{margin-top:10pt;margin-right:20pt;margin-bottom:30pt;margin-left:10pt}
C.
BODY{margin-top:10pt;margin-right:20pt;margin-bottom:30pt;margin-left:20pt}
D.
BODY{margin-top:10pt;margin-right:20pt;margin-bottom:30pt;margin-left:30pt}