Is that a weasel or a mink?

Did you see a weasel or a mink?

Would you call that a weasel or a mink?

I think I saw a weasel or maybe a mink?

Does that look like a weasel or a mink to you?

...Weasel or mink?

What word should we use to classify that animal: 'weasel' or 'mink'?