The answer is b because it wouldn’t make sense to have any of those other ones. hope it helps
Ok so no.1 horizontal is “SE”
2. Is VESTEN
Hello!
Im not sure if there is any other context, but the sentence means
"She's been dancing for three years"
If you mean correct as far as being a sentence.. and having a meaning, then yes, it is correct.
Hope this helps!
Have a great day!