Question

Is the example a complete sentence, sentence fragment, or run-on sentence? Once she found out about the dance contest.
a. run-on sentence
b. complete sentence
c. sentence fragment

Answer 1

c. sentence fragment because it's not a run-on sentence. Also, it's not a complete sentence because it doesn't say what she did after she found out about the contest. Your only choice left is a sentence fragment. 

Hope that helped:)

Answer 2

C) Sentence Fragment
Its not A) Run-on sentence because its not long enough
And Its not B) Complete Sentence, because it only says "Once she found out about the dance contest", its not a complete thought.  What did she do once she found about about the dance contest?