Section: Critical Reading Section 2

101) Vincent Chernof created ground-breaking musical works and they superimposed lovely melodies over dissonant harmonies.

1. works and they superimposed
   
2. works, which superimposing
3. works, they superimposed
   
4. works that superimposed
5. works, and superimposed
   

The sentence in its current format is a run-on sentence.