Final answer:
David Greybeard's visits to Dr. Goodall's camp show that the chimpanzees' response to her presence has changed over time.
Step-by-step explanation:
David Greybeard's visits to Dr. Goodall's camp show that the chimpanzees' response to her presence has changed over time. Initially, the chimpanzees were wary of Dr. Goodall and kept their distance.
However, as they became more familiar with her, they started to approach her and even interacted with her. This change in response indicates that the chimpanzees have become more comfortable with Dr. Goodall's presence and have developed trust in her.