To have a monopoly, barriers to entering the market must be so high that no other firms can enter. do network externalites create or remove barriers to entry? explain. network externalities

(a) create barriers to entry because a firm efficiently offers products that satisfy consumer preferences.
(b) remove barriers to entry because such externalities require multiple firms to provide the goods and services in the network.
(c) create barriers to entry because consumption of a firm's product decreases the value of goods and services produced by other firms.
(d) create barriers to entry because if a firm can attract enough customers initially, it can attract additional customers as its product's value increases by more people using it, which attracts even more customers.
(e) create barriers to entry because economies of scale are so large that one firm can supply the entire market at lower average total cost than can two or more firms.