To an economist, scarcity means that:
a. resources are unlimited but people's desires are limited.
b. a good is unavailable even at very high prices.
c. at a zero price, the available quantity of a good is insufficient to meet people's wants.
d. at the current market price, the amount available is less than the amount that people want and are willing to pay for.
e. it is very time-consuming to find a good.