Use the Following to Answer Question

Multiple Choice

Use the following to answer question:
-(Table: Demand and Total Cost) Use Table: Demand and Total Cost.Lenoia runs a natural monopoly firm 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.