Answer: The actual answer is A. Positive Feed-back.
Explanation: Took the test. Negative feedback loop is only to get the system back in balance. Positive is a positive response to the body. Such as creating a scab, or healing the skin.
Both climate change and humans were responsible for the extinction of some large mammals, according to research that is the first of its kind to use genetic, archeological, and climatic data together to infer the population history of large Ice Age mammals.