问题
单项选择题
Which of the following condition is least likely to be the reason that a black market is generally inefficient（）
A. Unenforceable contract.
B. Increased prices required by suppliers due to the risk of prosecution.
C. Intensive control by the government.
答案
参考答案：C
解析：
A black market is generally inefficient because: Contracts are not as enforceable. The risk of prosecution increases the prices required by suppliers. Quality control deteriorates, which leads to more defective products.