Final answer:
The company will have to invest the most in the knowledge base of the expert system.
Step-by-step explanation:
In building an expert system for stock trading with a very extensive amount of data to store, the company will have to invest the most in the knowledge base. The knowledge base stores all the information, rules, and algorithms that the expert system uses to make decisions. In the case of stock trading, the knowledge base would contain historical data, market trends, trading strategies, and other relevant information.
Learn more about investment in the knowledge base for an expert system in stock trading