Diffusion refers to .

A. the methodology for evaluating new product ideas
B. the second stage of the new product development process
D. the selection of opinion leaders to encourage product acceptance
E. how the use of a product spreads throughout a population
F. how promotion is used to support products throughout their product life cycle

E. how the use of a product spreads throughout a population

Explanation:

Diffusion is the process by which a new idea or new product is accepted by the market. The rate of diffusion is the speed with which the new idea spreads from one consumer to the next.

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explanation:

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