Consider the Following Statements Regarding the Economic Pricing Model

Multiple Choice

Consider the following statements regarding the economic pricing model:
I. The economic model is limited in use because a firm's demand curve is difficult to determine.
II. The marginal revenue and marginal cost model is valid for all forms of market organization (perfect competition, oligopoly, and so forth) .
III. Cost accounting systems are not designed to measure the marginal changes in cost incurred as production and sales increase.
Which of the above statements is (are) true?

A) I only.
B) III only.
C) I and III.
D) II and III.
E) I, II, and III.