Consider Firms Operating in an Industry Where the Own-Price Elasticity $\infty$

Consider firms operating in an industry where the own-price elasticity of demand is infinite; that is, E_Q,P = - $\infty$ .Use this information to determine the type of industry in which these firms operate and the optimal advertising-to-sales ratio.

A) perfectly competitive industry and $0.
B) monopolistically competitive industry and $ $\infty$ .
C) perfectly competitive industry and $ $\infty$ .
D) monopolistic industry and $0.