对市场需求与供应、建筑材料供应状况、项目所在地区的社会经济情况、项目地址及其周围环境、项目规划设计方案、项目进度、项目销售收入与投资估算、项目财务分析等属于详细可行性研究。（）

Which of the following describes a market for goods or services that operates outside the legal system, trading at prices that exceed legally imposed price ceilings（）

A. An incidental market.

B. A black market.

C. A utilitarian market.