问题详情

Intheforeignexchangemarket,whichismadeupofbanks"tradersandbrokers,prices(61)everyminute(62)tosupplyanddemand.Forsafety"ssake,abranchwillgetaratefromtheirtradersforabigtransaction.Thereforethetradersgivetheirbrancheslistsofexchangerates(63)theymaybuyandsellnotesandpaymentsinthemaincurrencies.
WheneverabankinBritainmakesapaymentinforeigncurrency,ormakesapaymentinsterlingtoanon-resident,thepaymenthasfirstto(64)underBritishexchangecontrolregulations.Thebankitselfcanusuallyauthorizethepaymentafterseeingadocumentsuchasaninvoicetoshowthatthepaymentisdue;butcases(65)borrowingandlendinghavetobereferredtotheBankofEngland.
(46)
A．alter
B．vary
C．turn
D．convert

请帮忙给出正确答案和分析，谢谢！