没看懂B错在哪里

问题如下：

Which portfolio includes a derivative that serves as a binding commitment to protect the value of the stock?

选项：

A.Stock and a short futures position B.Stock and a short call option position C.Stock and a short warrant position

解释：

A derivative is a financial instrument whose value is derived from an underlying asset. In the context of these portfolios, a short futures position acts as a firm commitment, as it obligates the holder to sell the underlying asset at a set price, thereby hedging against price decreases. Short calls and warrants offer different risk profiles and do not constitute firm commitments in the same way. 衍生品是一种金融工具，其价值取决于一个基础资产。在这些投资组合的背景下，空头期货头寸作为一种承诺，因为它要求持有人以设定价格出售基础资产，从而对冲价格下跌的风险。空头看涨期权和认股权证不属于远期承诺。