The correct statement about investment in human capital is:
There could be disadvantages to investing in human capital through education.
Investing in human capital, such as through education and training, can have disadvantages or drawbacks, such as high costs, time investment, and the potential for underemployment. The other statements also present potential challenges, but the correctness varies based on context and circumstances. For instance, while training often improves workplace safety, poorly designed training can potentially lead to safety issues. Similarly, there are various factors that determine the benefits of post-secondary education, and investing in health care generally aims to improve labor productivity rather than reduce it.