var vip,sale;
switch(vip){
case "钻石会员":
sale = 6;
break;
case "白金会员":
sale = 7;
break;
case "黄金会员":
sale = 8;
break;
default:
sale = 0;
}
以上代码，可以取代它的if语句是（）

A.if（vip=="钻石会员"）{sale=6；}else{if（vip=="白金会员"）{sale=7}else{sale=8}else{sale=0}}
B.if（vip=="钻石会员"）{sale=6；}elseif（vip=="白金会员"）{if（vip=="黄金会员"）{sale=8；}else{sale=0；}}
C.if（vip=="钻石会员"）{sale=6；}elseif（vip=="白金会员"）{sale=7；}elseif（vip=="黄金会员"）{sale=8；}else{sale=0；}