According to the James-Lange theory:

A) emotion is our perception of autonomic changes.
B) frustration leads to aggression.
C) intermediate arousal levels produce the best performance on difficult tasks.
D) the limbic system of the brain is critical for emotional behavior.

The James-Lange theory of emotion states that our perception of autonomic changes (physiological responses) leads to the experience of emotions. For example, we feel afraid because we perceive our heart racing and our palms sweating, rather than the other way around where we feel our heart racing because we are afraid.