Final answer:
Attribution theory is most useful in understanding a teacher's interpretation of a student's poor performance as it deals with the causes of behavior and events. Cognitive dissonance and other theories are less directly related to interpreting academic performance.
Step-by-step explanation:
Understanding a teacher's interpretation of a student's poor performance is most closely associated with Attribution theory. This psychological theory explores how individuals explain the causes of behavior and events. Attribution theory suggests that when analyzing a student's poor performance, a teacher might look to internal causes such as lack of effort or ability, or external causes, such as environmental influences or situational difficulties. This aligns with the broader educational psychology context.
By contrast, cognitive dissonance refers to the psychological discomfort from holding inconsistent beliefs, attitudes, or behaviors, and is less directly related to interpreting others' performance. The other theories listed, including the Cannon-Bard theory (which relates to emotions and physical reactions occurring simultaneously), Arousal theory (which discusses motivation and arousal levels), and Behavior theory (focusing on behaviors that are learned through interactions with the environment), are also less pertinent when it comes to interpreting a student's academic performance from a teacher's perspective.