As part of the courting season of lance-tailed manikins, a beta male f

As part of the courting season of lance-tailed manikins, a beta male follows the alpha male to the female, where they both perform a dance made of a complex series of stunts and flight displays. After the performance, only the alpha male mates, however. Researchers deduce that the beta male hopes to benefit by one day becoming an alpha male himself.

Which of the following, if true, most seriously strengthens the researchers' argument?


A. Research done by zoologists from 2006 to 2007, where manikin males were tagged the first year, then checked the following year, shows that both alphas and betas had the same status in 2007.

B. Bird watchers have reported that 30% of beta manikin males seen in the spring of 2006 were not found among the group in the spring of 2007.

C. Zoologists are recognizing the social benefits awarded to beta males by the group in a large variety of bird species.

D. Only 90% of lance-tailed manikin alpha males survive from one mating season to the next.

E. A genetic survey of the chicks born in the group's nests in 2006 and in nearby groups in 2007 has shown that 15% of the beta males which performed the dance in 2006 became alpha males of neighboring groups in 2007.