A ptarmigan is a ground-dwelling bird that changes colors with the seasons. In winter, ptarmigans are entirely white. In summer, their bellies are white, but their heads, backs, and wings are mostly brown. Where are ptarmigans most likely to be found?
areas with warm climates, such as the southeast United States
areas with mild, marine climates, such as those found along coasts
areas with hot, tropical climates, such as those found along the equator
areas with climates that vary throughout the year, such as the western United States