Final answer:
The sympathetic nervous system's fight-or-flight response, once crucial for survival in response to physical threats, is often triggered in the modern world by non-life-threatening stressors. This can lead to chronic stress, as the system is not meant for constant activation in response to the everyday challenges of modern human life.
Step-by-step explanation:
Scientists believe that the autonomic nervous system, and particularly its sympathetic division, may not be optimally adapted for the challenges of modern human life. The sympathetic nervous system activates the fight-or-flight response when we are faced with what it perceives as life-threatening situations. This was beneficial in prehistoric times when humans faced predators and needed to either flee or defend themselves. However, in today's world, stressors are more often psychological or non-life-threatening, such as work pressures or social situations.
Answer a) is correct: It triggers a fight-or-flight response, which may not be suitable for non-life-threatening stressors. This response includes physiological changes like increased heart rate and blood pressure, and the release of glucose and adrenaline into the bloodstream. These changes are not as relevant to modern stressors and can even be detrimental by contributing to chronic stress and associated health issues, as the sympathetic nervous system is not designed to be constantly activated, which is often the case in modern environments.