Reciprocity is a. when two or more people or groups oppose each other to achieve a goal that only one can attain. b. the idea that if you do something for someone then that person owes you something in return. c. the deliberate attempt to control a person by force. d. the state of balance between conflict and cooperation.

b.the idea that if you do something for someone then that person owes you something in return.

1.)dr. natterson- horowitz came to realize that their isn't much of a difference between animals and humans. just like humans, animals can suffer from illnesses and diseases like breast cancer, self injury, anxiety, and many more. she also discovered how they even treated and performed surgical procedures on animals just as if the animal it self were human. the los angeles zoo called dr. natterson- horowitz because they knew that she was a doctor and that  she would be able to recognize what was wrong with the gorilla. they knew that humans and gorillas were similar, so instead of calling another veterinarian, they called a doctor.