Humanistic theorists have been criticized for
a. underestimating the inconsistency of behavior from one situation to another.
b. overestimating the impact of childhood experiences on adult personality.
c. underestimating the inherent human capacity for destructive and evil behaviors.
d. overestimating the degree of similarity among people.

underestimating the inherent human capacity for destructive and evil behaviors.

Explanation:

Instinct -- it's something each and every individual is born with. It's not something we learn or something we see or something experience teaches us. For example, why someone likes strawberries, someone does not? Or why we pull away when a bad scent occurs? Why we blink? And many more. It's the same with violence -- someone is born with it in themselves, and someone, simply, is not.

if this is true of false i think it would be true

i agree d is most definitely correct!