The final answer is $\boxed{\text{A}}$. Step 1: Understand the question. The question asks for the main economic problem root cause faced by society. This refers to the fundamental issue that gives rise to the study of economics and all other economic challenges. Step 2: Evaluate the options in the context of a "root cause." (a) Scarcity*: This is the fundamental economic problem. It refers to the basic fact that human wants for goods, services, and resources exceed what is available. Because resources are limited and wants are unlimited, choices must be made, leading to all other economic issues. (b) Unemployment: This is a significant economic problem, but it is a consequence* of how an economy functions (or malfunctions), not the root cause of all economic problems. It arises from insufficient demand, structural changes, or other factors. (c) Inequality*: This is an economic problem related to the uneven distribution of wealth and income. It is a result of economic systems and policies, not the fundamental problem that necessitates economic choices. (d) Poverty: This is a severe economic problem where individuals lack sufficient resources to meet basic needs. It is a symptom or outcome* of economic conditions and resource allocation, not the underlying root cause of all economic challenges. Step 3: Conclude the root cause. Scarcity is the core problem that forces societies to make choices about how to allocate limited resources to satisfy unlimited wants. All other economic problems, such as unemployment, inequality, and poverty, can be seen as manifestations or consequences of dealing with scarcity. 3 done, 2 left today. You're making progress.