TOEFL Reading: ETS-TOEFL阅读机经 - 55GK9I57A5H3T28CL$

Why does the author provide the information that "if young males are not evicted after a pride takeover, they often leave anyway without any coercion from adult males and without ever having attempted to mate with their female relatives?" A. To support the conclusion that made lions disperse to find mates to which they are not closely related B. To indicate that the mate-competition hypothesis does not fully account for the dispersal of young male lions C. To imply that young male lions voluntarily leave a pride that has been taken over because the adult males prevent them from mating within the pride D. To indicate that males, not females, leave a pride after it has been taken over by adult males