Which of the following is the most important difference between observing users in a usability evaluation and observing them in a usability test? A. In an evaluation, the users pick the tasks they do. In a test, users are assigned tasks to do. B. In an evaluation, the users pick the location. In a test, users must go wherever the usability team is. C. In an evaluation, user feedback is not very important. In a test, user feedback becomes very important. D. There is no important difference between observing users in an evaluation and observing them in a test.