Final answer:
Increased emotional resilience is not a risk associated with prolonged exposure to stress in infancy, as chronic stress can lead to impaired cognitive development, weakened immune systems, and behavioral problems.
Step-by-step explanation:
Among the options listed, the one that is not a risk associated with prolonged exposure to stress in infancy is c) Increased emotional resilience. Exposure to chronic stress, especially during infancy, can severely impact a child's development. It can lead to impaired cognitive development and behavioral problems, and because chronic stress can suppress the immune system, it often results in a weakened immune system. Research in the field of psychoneuroimmunology has repeatedly demonstrated how chronic stressors negatively affect immune system function, increasing susceptibility to illnesses and infections. In contrast, increased emotional resilience is often seen as a positive outcome that arises from successfully overcoming challenges, not from prolonged exposure to adverse conditions like chronic stress.