GMAT Critical Reasoning (CR) | Re: The dwarf masked owl, a rare migratory bird of prey, normally makes it

hii , expert although i got the right answer for this and understood the above explanation , but somehow i am unable to eliminate option A, don't know why but when i negate it , it seems that if there are some birds of prey who also live in spiny cactus then owl might change their mind and they will not make home for the winter , isn't it also a assumption ? i think i am overthinking ): please help to understand

thanks