Consider the market shares below for the top 10 firms in a market. Based upon our discussion of the concdentration ratio, what would be the best characterization of this market? Firm 1 has 12% Firm 2 has 7% Firm 3 has 5% Firm 4 has 4% Firm 5 has 4% Firm 6 has 3% Firm 7 has 2.5% Firm 8 has 2% Firm 9 has 2% Firm 10 has 2% Group of answer choices The market is a tight oligopoly The market is effectively competitive The market is a loose oligopoly The market is effectively a monopolist