Final answer:
In humans, females experience a unique long postreproductive lifespan not seen in gorillas, elephants, or whales. The correct answer to the question is B. Humans.
Step-by-step explanation:
A long period of female postreproductive time, also known as a postreproductive lifespan, is a unique characteristic only found in humans. While other animal species, such as gorillas, elephants, and whales, do provide significant parental care following reproduction, they do not experience a similar lengthy period of postreproductive life as humans do. Human females can live for decades after they have stopped being fertile, which is not the case in the other animals listed.