When is innovation considered useful rather than merely an attractive idea?

Correct answer: When it solves a problem and creates value

Innovation becomes useful when it addresses a real problem or need and provides value to customers or society. Value may appear through better quality, lower cost, greater convenience, or a new solution. An idea is not useful merely because it is expensive, unusual, or difficult to understand. Therefore, option A correctly identifies problem-solving and value creation as the key tests of useful innovation.