Final answer:
The correct answer is D) Traumatic stress response, which refers to the psychological and neurobiological effects following traumatic events. Studies show that such experiences can result in long-term alterations in brain function and behavior, often linked to mood disorders.
Step-by-step explanation:
The phenomenon where witnessing a murder at a young age affected Sally's brain development and behavior throughout her life is best defined as D) Traumatic stress response. This term encompasses the psychological and neurobiological changes that occur following exposure to traumatic events, such as witnessing a murder.
Research in both humans and animals, like the study mentioned involving rats by Raineki, Cortés, Belnoue, and Sullivan (2012), show that early-life negative experiences can alter the function of the amygdala, which is part of the brain's limbic system involved in emotion regulation and can result in patterns of behavior that mimic mood disorders, including depression.