Use the Following to Answer Questions

Multiple Choice

Use the following to answer questions:
-(Table: Demand and Total Cost) Look at the table Demand and Total Cost. Lenoia runs a natural monopoly producing electricity for a small mountain village. The table shows Lenoia's demand and total cost of producing electricity. The marginal revenue of the fourth unit of production is:

A) $200.
B) $250.
C) $450.
D) $500.