Rwanda's Scientific Understanding of Student Preferences

Explanation:

Rwanda has achieved the level of description in scientific understanding. By observing and recording the student's favorite items during free play, Rwanda is describing the behavior and preferences of the student. This level of scientific understanding involves accurately documenting and describing the observed phenomenon. The other options in the question: a. Paired stimulus preference assessment, b. Prediction, and c. Free operant preference assessment, are different methods used in psychological research to understand preferences and behaviors in individuals. However, in this specific case, Rwanda is simply documenting and describing the student's favorite items without necessarily making predictions or using specific assessment techniques.