Zoos Often Loan Animals to Other Zoos for Breeding Purposes

Zoos often loan animals to other zoos for breeding purposes. From an evolutionary standpoint, what is the benefit?

A) New animals increase zoo revenues.
B) It increases the genetic diversity of the zoo's population.
C) It increases the effects of natural selection on the population.
D) It increases the rate of random mutations.
E) It creates a bottleneck effect.