The source of all economic problems arises from scarcity. Scarcity refers to the limited availability of resources in comparison to the unlimited wants and needs of individuals. This means that there are limited resources available to produce goods and services, so we have to make choices about how to allocate these resources in the most efficient way possible. This leads to the concept of opportunity cost, which is the cost of the next best alternative that must be given up in order to pursue a certain action or decision. The scale of preference refers to an individual's ranking of their wants and needs, and helps to determine how they allocate their limited resources. Ultimately, the root of all economic problems stems from the fact that resources are scarce and we must make choices about how to best use them to satisfy our unlimited wants and needs.