Final answer:
The 'invisible hand' refers to how c. individual self-interest in a market economy unintentionally achieves broader social good, resulting in a trend towards equilibrium without centralized planning or government intervention.
Step-by-step explanation:
The term “invisible hand” refers to the concept that individual self-interest in a free market economy leads to outcomes that can benefit society as a whole, often without intention.
This idea was popularized by economist Adam Smith, who suggested that as individuals pursue their own interests, they inadvertently contribute to the economic well-being of the whole society. This coordination is achieved not through deliberate planning or government intervention but through the collective effects of individuals’ actions seeking to maximize their own gains.
The correct answer to the student's question is C) Individual Self-Interest. This intrinsic mechanism of the market economy guides resources to their most valuable use, as if dictated by an 'invisible hand' leading to a trend towards equilibrium.