Final answer:
Improving the quality of job-training programs is the correct answer for achieving increases in human capital. Building factories, increasing government spending on infrastructure, increasing physical capital per worker, and reducing skilled immigration are not directly related to enhancing human capital.
Step-by-step explanation:
Increases in human capital can be achieved through various methods, particularly those that contribute to upgrading the skills, knowledge, and overall capabilities of the workforce. According to the options provided, human capital can be increased by improving the quality of job-training programs (a). These programs provide workforce participants with advanced skills and knowledge that directly enhance their productivity and economic value. Investments in human capital are crucial for economic growth and are equally as important as investment in physical capital and technology.
Building more factories (b), increasing government spending on infrastructure (c), and increasing the physical capital per worker (d), are all activities related to physical capital rather than human capital. Reducing immigration of skilled workers (e) could potentially reduce the available human capital within an economy, as it may limit the influx of individuals with valuable skills and knowledge.
Government investment in education and training is a common method to improve human capital, contributing to a more skilled and knowledgeable workforce, which in turn supports higher economic growth rates. This is especially significant for low-income nations, where such investments can make a profound impact on productivity and development.