关于进度款的支付，下列说法错误的是（）。

A．发承包双方应按合同约定，根据工程计量结果，办理期中价款结算，支付进度款

B．进度款支付周期，应与合同约定的工程计量周期一致

C．工程进度是发包人向承包人支付进度款的前提和依据

D．计量和付款周期可采用分段或按月结算的方式

The field of medicine has always attracted its share of quacks and charlatans — disreputable women and men with little or no medical knowledge who promise quick cures at cheap prices. The reasons why quackery thrives even in modern times are easy to find.To begin with, pain seems to be a chronic human condition. A person whose body or mind "hurts" will often pay any amount of money for the promise of relief. Second, even the best medical treatment cannot cure all the ills that beset men and women. People who mistrust or dislike the truths that their physicians tell them often turn to more sympathetic ears.Many people lack the training necessary to evaluate medical claims. Given the choice between (a) a reputable physician who says a cure for cancer will be long, expensive and may not work at all, and (b) a salesperson who says that several bottles of a secret formula "snake oil" will cure not only cancer but tuberculosis as well, some individuals will opt for "snake oil".Many "snake oil" remedies are highly laced with alcohol or narcotic drugs. Anyone who drinks them may get so drunk or stoned that they drown their pains in the rising tide of pleasant intoxication. Little wonder that "snake oil" is a popular cure-all for minor aches and hurts! But let there be no misunderstandings. A very few "home remedies" actually work. However, most remedies sold by quacks are not only useless, but often can be harmful as well.

Quackery thrives even in modern times because________.

A．patients pay any amount of money

B．patients do not like their physicians

C．quacks say that they can help patients

D．best medical treatment costs very much