optionallyadv.可选择地optionaladj.任选的optional stop order任意停机指令optional regrouping优化组合optional parametersn.可选参数optional processing[计] 任选处理, 选择处理optional attendance自由参加optional facilities任选设施optional redemption[经] 选择提前赎还的权利optional additional选港附加费optional reinsurance临时再保险optional constituent可选成分