For a Natural Monopoly to Exist

Multiple Choice

For a natural monopoly to exist,

A) a firm must continually buy up its rivals.
B) a firm's long-run average cost curve must exhibit diseconomies of scale beyond the economically efficient output level.
C) a firm's long-run average cost curve must exhibit economies of scale throughout the relevant range of market demand.
D) a firm must have a government-imposed barrier.