Why is Snow White a tale of terror rated r?

Snow White is a classic fairy tale and is not typically rated R or considered a "tale of terror". It is a story that is often told to children.

It's possible you are thinking of a specific adaptation of Snow White that may have a darker, more mature tone, which could warrant an R rating. However, the original story is not generally considered to be scary.

If you could provide more details about which version of the story you are referring to, I could give you a more specific answer.