What physiological response occurs when facing a threatening situation?

When an individual encounters a threatening situation, the body initiates a physiological response known as the "fight or flight" response. This response is characterized by the release of stress hormones, predominantly adrenaline (also known as epinephrine) and cortisol. These hormones prepare the body to react quickly to the threat, enhancing physical performance by increasing heart rate, blood pressure, and energy supplies. This biological reaction boosts awareness and can improve physical capabilities in high-stress situations, which is essential in defensive tactics scenarios.

The other options refer to physiological responses that are not the primary reactions to threat. For example, endorphins are typically released in response to pain or stress as a means of pain relief and promoting a sense of well-being, but they are not the main hormones involved in immediate threat response. Similarly, while adrenaline is a significant player in the fight or flight response, it is not released in isolation; it works in conjunction with other stress hormones. Finally, serotonin is primarily associated with mood regulation and does not play a critical role in immediate physical responses to threats. Therefore, the answer regarding the release of stress hormones encompasses the body's comprehensive strategy to effectively handle threatening situations.