Four stages of creative thinking are :

Correct option is D

The four stages of creative thinking as identified by Graham Wallas are Preparation, Incubation, Illumination, and Verification. During preparation, the problem is defined and explored. Incubation allows subconscious processing. Illumination is the "aha" moment, and verification ensures the idea is feasible.
Information Booster:
1. Preparation: Initial understanding and research.
2. Incubation: Period of unconscious reflection.
3. Illumination: Sudden insight or solution.
4. Verification: Evaluating and refining the solution.
5. Commonly used in problem-solving and innovation.
Additional Knowledge:
 (a) Illustration: A misnomer in creative process stages; often confused with presenting ideas.
 (b) Intuition: May aid creativity but is not a distinct stage.
 (c) Involvement: Implies engagement, but not a formal creative stage.