The author mentions the peacock's tail in line 8 most probably in order to A. cite an exception to the theory of the relationship between intrasexual selection and male competition B. illustrate the importance of both of the pathways that shaped the evolution of birdsong C. draw a distinction between competing theories of intersexual selection D. give an example of a feature that may have evolved through intersexual selection by female choice E. refute a commonly held assumption about the role of song in mate attraction