Answer:
A Change in climate.
Explanation:
"Snowy" or better yet Arctic animals survive better in colder climates, So if their home gets warmer they will move towards colder weather. But if you want another example they will also leave if there is little to no food.
Interneurons are sensory Afferent neurons. Specialized to detect stimuli and transmit information about them to the Central Nervous System. So i would go with A and B
To act as a catalyst in chem reactions