The increase in capital stock is primarily associated with which of the following economic activities?

The increase in capital stock is primarily associated with investment. Investment refers to the purchasing of capital goods that can be used to produce goods and services in the future. This includes everything from machinery and buildings to technology and infrastructure. When businesses invest in these assets, they enhance their productive capacity, which can lead to greater output and efficiency.

Investment plays a crucial role in economic growth, as it leads to an increase in the total capital stock within an economy. A larger capital stock typically means that an economy can produce more goods and services, therefore driving growth. In contrast to other activities listed, consumption refers to the use of goods and services by households, exports relate to the sale of domestically produced goods to foreign countries, and manufacturing involves the actual production of goods. While all these activities are important to the economy, only investment directly results in an increase in the capital stock.