What is human capital? what is a common effect of investing in human capital?

Human capital is a measure of the economic value of an employees skill set. and the effect is that it can improve the employee and the economic value as a whole when invested in

Human capital is the stock of skill and productive knowledge embodied in people of a country.A common effect of investing in human capital is that it yields a good return in future. Higher incomes can be earned because of higher productivity of the more educated or the better trained persons, as well as the productivity of healthier people. Not only do the educated and the healthier people gain through higher incomes, indirectly the society also gains due to the advantages of a more educated or a healthier population.

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Prioritizing is the answer

Iwould say either b or ci could be wrong let me know