[单项选择]A. However, the term is also commonly used for markets in which economic intervention and regulation by the state is limited to tax collection, and enforcement of private ownership and contracts. Free markets differ from situations encountered in controlled markets or a monopoly, which can introduce price deviations without any changes to supply and demand.
B. A free-market economy is one within which all markets are unregulated by any parties other than market participants. In its purest form, the government plays a neutral role in its ad ministration and legislation of economic activity, neither limiting it nor actively promoting it.
C. By definition, buyers and sellers do not coerce each other, in the sense that they obtain each other’s property rights without the use of physical force, threat of physical force, or fraud, nor are they coerced by a third party.
D. Where substantial state intervention exists, the market is a mixed economy. Where the state or co-operativ