Which of the following is NOT one of the four Cs?

The four Cs are a framework commonly used in user experience design, which typically includes Clarity, Consistency, Context, and a fourth element that may vary based on different interpretations. In this case, Clarity is indeed one of the four Cs, meaning that selecting it as not part of the framework is incorrect.

The correct answer is that 'Complementary' is not recognized as one of the four Cs in the traditional user experience design context. Clarity refers to the need for clear communication and understanding in design, ensuring that users can easily grasp the purpose and instructions of an interface. Consistency emphasizes uniformity across design elements and experiences, helping users make connections and predict outcomes when interacting with products. Context highlights the environment in which the user interacts with the design, ensuring that it meets the situational needs and expectations of the user.

Thus, 'Complementary' does not fit into the standard four Cs framework, clarifying its status as the correct response.