Which of the following best defines the term: product life cycle?
◦ the time span between when the company begins the initial R&D on a product till the time when the first unit is sold.
◦ the span of time from initial R&D on a product to when the customer service and support for the product is no longer offered
◦ the time span between when the company begins the initial R&D on a product till the time when the last unit is sold
◦ the span of time from when the first unit of the product is sold until the last unit of the product is sold