With Diffusion of Innovation

With diffusion of innovation:

A) once a product enters the market, very similar products will enter within a very short period of time.
B) one new product will produce ancillary product invention (e.g., video cassettes created a market for cassette holders) .
C) not all consumers accept a new product at the same time because adoption of a product spreads slowly throughout the population.
D) product changes by one competitor lead to similar product changes by another competitor.