The correct answer is: D. downward sloping to the right
A commodity, the price of which has risen but is expected to become scarce, will present a demand curve that is downward sloping to the right. This is because, as the price of a commodity rises, people will be less willing to buy it. However, if the commodity is expected to become scarce, people will be more willing to buy it, even at a higher price. This is because they know that the price will continue to rise in the future, so they want to buy it now while they still can.
The other options are incorrect because they do not accurately reflect the relationship between price and demand. A regressive demand curve is one in which demand decreases as price decreases. This is not the case for a commodity that is expected to become scarce. A kinked demand curve is one that has a sharp bend in it. This is not the case for a commodity that is expected to become scarce. A downward sloping demand curve is one in which demand decreases as price increases. This is the case for a commodity that is expected to become scarce.