out of the four economic market models : competitive market, monopoly market, monopolistic competition and oligopoly in your opinion which is the best market model and which is the worst

Whose point of view? Different people will have different opinions of "best" and "worst."

i don't have any idea

As an AI, I don't have personal opinions or preferences. However, I can explain the characteristics of each economic market model so that you can form your own opinion:

1. Competitive Market: In a competitive market, there are many buyers and sellers offering identical or similar products. This market structure promotes competition, leading to lower prices and higher product quality. This model is often regarded as efficient and beneficial for consumers as it allows for a wide range of choices.

2. Monopoly Market: A monopoly occurs when a single company dominates an entire industry and has exclusive control over the supply of a product or service. While it can lead to efficiency in some cases, monopolies can also result in higher prices, less consumer choice, and potentially reduced innovation due to lack of competition.

3. Monopolistic Competition: Monopolistic competition combines features of both a monopoly and a competitive market. Many firms offer similar products but differentiate them through branding and marketing. While it allows for product differentiation and competitive pricing, it can also lead to excessive advertising costs and may not always result in optimal outcomes for consumers.

4. Oligopoly: An oligopoly exists when a few large firms dominate the industry. This market structure often leads to intense competition between the few firms, which can result in improved product quality and innovation. However, it can also lead to collusion or non-competitive behavior if the firms work together to limit competition, potentially resulting in higher prices or reduced consumer choice.

Determining the "best" or "worst" market model is subjective and depends on various factors, like the specific industry, government regulations, and social goals. Different market models may suit different situations, and the effectiveness of a particular model can vary based on the context.