A working model of the start-up product, prior to commercialisation, is usually called: Industrial design Consumer design Prototype None of the above

The correct answer to the question is Prototype.

A prototype is a preliminary model of a product that demonstrates its functionality and design, allowing for testing and feedback before the final product is manufactured and commercialized. Prototypes are essential in the development process as they help to evaluate and refine the product concept, ensuring that it meets the needs of potential users and adheres to design specifications.

In contrast, industrial design refers to the design of products that are to be manufactured, while consumer design focuses more on the usability aspects for consumers. "None of the above" does not apply since "Prototype" is indeed a valid term in this context.