Answer:
The correct answer is the third option: Investments in human capital.
Step-by-step explanation:
To begin with, the neoclassical economics focus mostly in the study of the economy by paying most of the attention to the individual parts of it, saying that, this science accepts a methodological individualism and it focus in a rationality at long term and that is why it basically would find the investment in human capital as an element that would underpins long run productivity growth in the economy. Moreover, there is a principle in a neoclassical theory that states that the individuals act over the bases of complete and relevant information and therefore that it must focus on them primarily by investing in them.