What kind of pets? 1, 2, or 3 may be reasonable for cats or dogs, but 5 to 25 might be reasonable for tropical fish -- depending on the size of your tank. I have no idea what a reasonable number of pigeons might be. Then again, I know a guy who keeps an ant farm.
And then who gets to decide what is "most reasonable"? This is an opinion question with no right (or wrong) answer.
John
My calculator said it, I believe it, that settles it