单选题 The passage is primarily concerned with

• (A) contrasting the role of domination and courtship in determining the evolution of bird plumage
• (B) illustrating the effectiveness of a particular approach to categorizing various evolutionary innovations
• (C) documenting the origins of a currently accepted scientific theory about food and courtship
• (D) proposing a new explanation for the evolutionary reasons behind the ornamentation of male bird plumage
• (E) showing that physical adaptation plays an integral role in contributing to species identification of birds