Suppose a Perfectly Competitive Market Is in Long-Run Equilibrium and Then

Suppose a perfectly competitive market is in long-run equilibrium and then there is a permanent increase in the demand for that product. The new long-run equilibrium will have

A) fewer firms in the market.
B) more firms in the market.
C) the same number of firms in the market.
D) a permanent decrease in supply.
E) probably a different number of firms, but it is not possible to determine if there will be more or fewer firms.