Compared to the purely competitive industry, a pure monopoly: a) is often more efficient from society's perspective because it has big plants and it uses the newest technology.
b) will always become competitive in the long run because positive economic profits will entice competitors into the market.
c) produces an equal amount of output, but charges higher prices to cover all costs in the market.
d) is able to use barriers to entry and maintain positive economic profits in the long run.