In Answering the Question, Assume a Graph in Which Dollars

In answering the question, assume a graph in which dollars are measured on the vertical axis and output on the horizontal axis. For a purely competitive firm,

A) marginal revenue will graph as an upsloping line.
B) the demand curve will lie above the marginal revenue curve.
C) the marginal revenue curve will lie above the demand curve.
D) the demand and marginal revenue curves will coincide.