D: food availability for the moose and disease for the wolf
It would be called a biome, like a tundra or a desert.
Answer - B
Fish and reptiles both are ectothermic but fish have gills and reptiles have lungs. Ectothermic organisms do not have an internal mechanism of regulating their body temperature and are dependent on their atmosphere for temperature regulation. Fish, reptiles and invertebrates are examples of ectothermic organisms.