the purpose is simple, if you have a dog, what is it, a cat, a bird, and anything else you may have.
if you COULD have a dog which breed would you class as your favorite, same goes for cats and birds.
dog, border collie
cat (have) Persian, wouldnt mind a russian blue or british shorthair
bird, a parrot species ideally, preferably a king parrot or a sulphur crested cockatoo