Hello!
The correct answer would be option C. since it is describing something/someone.
Hope this helps and have a great day! :)
Assuming that in the last option 'whichever melody you create' is underlined, the correct answer is that one, the last sentence. Because this is the only sentence in which 'to' is used as a preposition, in 2 and 3 there are no prepositions, and in 1 'to' is a part of an infinitive phrase.