b这句话我好像学过，他想表达什么，为什么是错的呢

问题如下：

The law of one price is best described as:

选项：

the true fundamental value of an asset.

earning a risk-free profit without committing any capital.

two assets that will produce the same cash flows in the future must sell for equivalent prices.

解释：

C is correct.

The law of one price occurs when market participants engage in arbitrage activities so that identical assets sell for the same price in different markets.

A is incorrect because the law of one price refers to identical assets. B is incorrect because it refer to arbitrage not the law of one price.

中文解析：

一价原则描述的是一种关系，即同样的商品在不同市场也应该卖一样的价格。

produce the same cash flows，会产生相同的现金流，即可认为在收益层面上这是相同的商品 。