I believe it is D! I hope this helps : )
Answer: Toddlers have pot bellies because they have underdeveloped stomach muscles, so losing the pot belly would be because of muscle development.
Explanation:
According to the cognitive arousal theory of emotions, appraisal of the situation would come before the physical arousal and the experience of emotion. According to the theory, when an emotion is felt, a physiological arousal normally occurs and the person uses the immediate environment to search for the emotional cues to label the physiological arousal.