Final answer:
Online music file sharing services are a substitute threat to the music industry in Porter's five forces model as they provide a cheaper and more convenient alternative to traditional music purchasing methods. The correct option is A.
Step-by-step explanation:
True. Analyzed in terms of Porter's five forces model, online music file sharing services do represent a threat to the music industry in the form of a substitute product. Porter's model assesses the competitive environment of a business and one aspect of this model examines the threat of substitutes.
Online music file sharing services can be seen as a substitute because they allow consumers to access music without purchasing it directly from traditional music providers, such as CD retailers or digital music stores. This can lead to reduced sales and profits for these traditional music businesses due to the competition from a more convenient or cheaper product.