Which of the following is an acute response to stress?

An acute response to stress is characterized by immediate reactions that occur in response to a perceived threat or crisis. Panic, for instance, is a rapid emotional and physiological response that can manifest when an individual is suddenly confronted with a stressful situation. This immediate panic can involve increased heart rate, heightened alertness, and a surge of adrenaline, all of which are part of the body's fight-or-flight response. This response helps an individual react quickly to danger, making it a clear example of an acute reaction.

On the other hand, the other options represent more chronic or evolving responses to stress. Persistent anxiety and long-term depression indicate ongoing mental health issues that develop over time rather than immediate reactions. Gradual acceptance of loss suggests a process of coping and adjustment that unfolds, reflecting a longer-term emotional experience rather than the acute response defined in this question. Thus, immediate panic during a crisis is the only option that aligns with the concept of an acute response to stress.