Final answer:
Avoidance option a is correct the behavioral symptom of anxiety among the given options. While irritability and excessive worry are related to anxiety, they are not behavioral symptoms. Poor sleep, often a result of anxiety, is considered a physical symptom.
Step-by-step explanation:
The behavioral symptom of anxiety mentioned in the options provided is A.) Avoidance.
Avoidance behaviors are common among those suffering from anxiety as individuals may steer clear from situations or activities that they anticipate will trigger their anxiety. This can manifest in different aspects of life, including social interactions or specific tasks.
While options B.) Irritability and C.) excessive worry are also associated with anxiety, they are generally categorized as emotional or cognitive symptoms rather than behavioral. Option D.) poor sleep, although often a consequence of anxiety, is more of a physical symptom. Anxiety can affect learning and school attendance, as heightened worry and stress might lead to avoidance behaviors, further affecting a student's ability to engage with educational settings or social situations.