Ernie Created a Product That Let People Record Television on a Digital

Ernie created a product that let people record television on a digital recorder while they were watching it. At first, very few people bought the product, but one year later the product started selling so much that stores could not keep them in stock. This illustrates the concept of .

A) critical break
B) exploding diffusion
C) quick diffusion
D) innovation milestone
E) the tipping point