According to Karl Marx, the ultimate source of profits from capitalists is <u>B. exploitation of workers</u>.
<h2>Explanation:</h2>
Karl Marx believed that the labor cost that is given to the workers is way too less for the value they add to the product. He proposed that the profit that is earned by the capitalists comes only because the workers are not given the worth of their work.
If the workers are given as much value they add to the product, in the end, there would no profit left for the capitalist to fetch.
According with Karl Marx the source of capitalism profit is all related to how labor is paid and explored. His ideas highlight the power of labor and how capitalism keeps a system of social classes based on labor exploration for production of goods and services for profit of just some people.