Which of the Following Statements Regarding the Valuing of Costs

Which of the following statements regarding the valuing of costs and benefits is NOT correct?

A) Because competitive markets exist for most commodities and financial assets, we can use them to determine cash values and evaluate decisions in most situations.
B) The first step in evaluating a project is to identify its costs and benefits.
C) In the absence of competitive markets, we can use one-sided prices to determine exact cash values.
D) Competitive market prices allow us to calculate the value of a decision without worrying about the tastes or opinions of the decision maker.