What are the two types of integration that can allow monopolies to happen

Horizontal & vertical Integration.

Explanation:

In Horizontal integration, One business will make series of efforts to Acquire other business organizations that operate in a similar market. This will eventually eliminate any competitors in the market and created the monopoly.

In a vertical integration, one business will make series of efforts to acquire other companies that's involved in the production chain.

(For example , If you own a business that sell fried chicken, you conduct a vertical integration by acquiring farms that produce the chicken, the oil, the companies that make spices/seasoning , etc.)

By acquiring those companies, that one business entities will be able to keep the cost of their production very low, leading to a low selling price of that product. This will make the majority of the consumers to choose that one business over any other competitors and create a monopoly.

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