Answer: B. doesn't exist
Step-by-step explanation:
A Monopoly has no defined Supply Curve. This is as because they are PRICE MAKERS instead of PRICE TAKERS they can set the price, not take whatever price is there.
The Supply Curve essentially denotes the various prices and quantities that a company will sell at. In other words, for a certain price, suppliers will produce a certain amount.
Monopolies do not care for such since they set the price and the output is based on the demand curve.
For this reason they do not have a Demand Curve.