What is the main idea behind the human capital theory?

The main idea behind human capital theory is that individuals invest in their own education and training to enhance their skills and knowledge, which in turn increases their potential for higher income and better career opportunities. This theory posits that education is viewed as an investment, much like purchasing equipment or property, where the goal is to improve an individual's productivity and earnings over time. Higher education and skills lead to better job prospects and overall economic advancement for the individual.

The other options address different aspects of career development but do not encapsulate the core principle of human capital theory. For example, factors like chance or family background may influence career trajectories, but they do not emphasize the proactive steps that individuals take to improve their marketability through education and training. Thus, these alternatives do not relate directly to the investment in personal development and skills enhancement that is central to human capital theory.