Network effects arise in industries where:

a$.$

the size of the network of complementary products is a primary determinant of demand for an industry's product.

b$.$

companies that are not in favor of a technical standard network together.

c$.$

companies network together and lobby for establishing certain technical standards.

d$.$

a large network of companies in an industry use the same business model and strategies.

e$.$

a company adheres to the same technical standards across its network of outlets.