The attribution made by Javiar is an example of an attribution that is internal, stable and controllable**.
This is internal because he attributes his success on the AP exam to his personal efforts and dedication in studying throughout the year. He believes that his own actions, such as consistent weekly studying, played a role in his achievement.
It is stable because he mentions that he poured all his extra time into studying for the exam over the last month. This suggests that he sees his study habits and dedication as relatively consistent and enduring factors contributing to his success.
As well, it is controllable because Javiar's attribution implies that he had control over his study habits and the effort he put into preparing for the AP exam