Final answer:
An attractive idea must be developed into a product concept.
Step-by-step explanation:
The answer to the question is B) product concept.
An attractive idea must be developed into a product concept. Design concepts are a set of possibilities for solving a design problem. They are created by brainstorming alternative solutions and exploring different ideas. Once the concepts are evaluated and compared using criteria and constraints, the best concept is chosen to move forward with the product design.