Final answer:
An economy operating efficiently (choice c) means it cannot produce more of one good without producing less of another, reflecting the concept of productive efficiency on the production possibilities frontier.
Step-by-step explanation:
If an economy is operating efficiently, the correct answer to the given question is option c: It is not possible to produce more of one good without less of another good. This concept is tied to the idea of productive efficiency and the production possibilities frontier (PPF). Operating on the PPF means that an economy is using its resources to the fullest potential. Therefore, if more of one good is produced, resources would have to be reallocated from the production of another good, causing its output to decrease.
Scarcity is a fundamental economic problem where wants exceed what can be made from all available resources at any given time. This means that option b is incorrect, as scarcity cannot be eliminated in a real-world economy since resources are limited; people must make choices related to goods and services, and it's through these choices that resources are allocated.
Therefore, achieving productive efficiency does not imply that the rich and poor have adequate access to goods and services (option a) or that the production of goods cannot be increased in any way (option d). It rather implies that the economy cannot produce more of a particular good without sacrificing some quantity of another good due to its resource constraints.