like humans, animals including dogs and cats get goose bumps. on a cold day, these goose bumps cause their coats to expand creating a layer of insulation. if the animal is scared, the coat will also expand making the animal look larger to predators. these responses serve as examples of

detection and response to stimuli

Explanation:

Generally, the chills are related to concentrations of energy that can run through our bodies and animals. During the day, we come into contact with various energy sources and exchange energy from our body with these external sources. In this case, the shiver occurs when our body comes into contact with energy fields with different intensity than our body has. That's why we shiver in the cold.

However, the shiver can also be considered a process of detection and response to stimuli, for this reason, we get goose bumps not only in the cold, but when listening to good music, and when reading something impactful for example. In addition, animals may experience chills as a response to receiving a threatening stimulus.

well for one plants are always the producer, so a is the answer. a wolf is more of the consumer(predator) and the deer is the prey so i know those two are out of the question. also mushrooms are fungi/fungus so a is the producer.