At Xiehe Building Materials Co. , Ltd. in a certain county, a worker accidentally wasted more while using brick-making raw materials, and one of his colleagues who had a good relationship turned out to be angry. The manager said that this kind of thing is quite common now Workers with poor labor discipline have become the target of public criticism. In the past, it often occurred that equipment was not repaired and the newly purchased brick-making machine was destroyed in less than one year. In 1993, the company was reorganized into a joint-stock company, at 2.1 million yuan. Among the total shares, employees individually invested 1 million yuan. The enterprise connected employees through asset bonds, and employees were both shareholders and laborers, and their enthusiasm was unprecedentedly high. What is the main point supported by this passage? ['The shareholding system can change the interest relationship between employees and enterprises.', "The shareholding system plays an important role in mobilizing workers' production enthusiasm.", 'The joint-stock system can control the waste and looseness of enterprises.', 'The production disciplinary effect of serious joint-stock enterprises is obvious.']