Read the following essay:

"The cold and hunger that come with winter pose serious threats to wildlife. Animals have only three options: they must migrate, hibernate, or tolerate. These very different strategies make it possible for life to survive in even the most brutal environments.

"Migrating animals move to lower elevations or warmer regions where winter conditions aren’t as harsh. This sounds simple, but many migrations are long, difficult, and dangerous. Animals must be able to find food and water along the way, which becomes ever more uncertain in the face of habitat loss and climate change.

"Hibernating animals stay in the same place all year long. In winter they find a sheltered spot, hunker down, and slow their metabolism enough to basically sleep through the season. It’s an appealing strategy, but also a risky one. Animals have to store enough fat in the fall so that they can live without eating for several months. If they don’t eat enough, they’ll starve before spring.

"Animals that tolerate winter without moving out or shutting down use a number of tricks to survive, from changing color to blend with the snow to growing thick layers of fat, fur, and feathers for insulation. Their lives depend on finding and storing food at a time when most of those resources have fled or gone dormant."

Choose the outline that best shows the main idea and major details of this reading.