Which of the following is NOT a type of eagle?

The choice indicating "Horseshoe Eagle" is correct because it refers to a bird that does not exist within the recognized varieties of eagles. The Golden Eagle, Bald Eagle, and Steller's Sea Eagle are all well-documented species, each belonging to the family Accipitridae and noted for their distinctive characteristics and habitats.

The Golden Eagle is renowned for its agility and speed, often found in mountainous regions. The Bald Eagle, a national symbol of the United States, is easily identifiable by its white head and tail contrasted against its dark brown body and wings. The Steller's Sea Eagle, one of the world’s heaviest eagles, is found primarily in coastal regions of northeastern Asia and is known for its striking appearance and feeding habits.

In contrast, the term "Horseshoe Eagle" does not classify any recognized type of eagle; therefore, it stands out as the correct answer to the question. This reinforces the importance of familiarity with avian classification and the characteristics that define specific species within ornithology.