The industry elasticity of demand for birthday party favors is -2 while elasticity of demand for a representative firm in this industry has an elasticity of demand of -20 and firms in the industry have identical market shares. Based on Rothschild approach to measuring market power we concede that

A. There's no monopoly power in this industry

B. The Herfindahl Index for this industry is 1000

C. The industry might as well be an example of monopolistic competition

D. The Rothschild index for this industry is 10%

E. All of the above