Please choose the correct ending to complete the given sentence: Health: [header] How to improve your stress response [title] Recognize when you're stressed. [step] In order to effectively manage stress and improve your stress response, you must first learn how to identify stress. It is possible to spend such a long time in a stressed state that you no longer know how to recognize it.

Ending1: [substeps] The fight-or-flight, or stress response, typically involves muscle tension, a rapid heartbeat, and shallow breathing. Other signs that you may be stressed are demonstrated in how you react to certain events. Ending2: Try starting off by recognizing when you're in a stressful state and help you identify when you're feeling it. [substeps] A typical state of mind for a teen is to feel stress when they come home from school. Ending3: Stressful sources of stress are things like work or school or personal relationships. [substeps] Your life is often occupied with personal interests, hobbies, tasks, or things that cause you stress. Ending4: If you already have trouble with stress, you likely identified the trigger when you began to engage in some of your behaviors. Identify the triggers that are causing your stress, by recognizing them and watching a series of videos and books about your triggers.

Answer format: ending1/ending2/ending3/ending4