Respuesta :
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.
The object of a preposition is a noun that comes after a preposition, so the sentence that has a noun clause after a preposition is
To play different styles of music in my band is what I would like to do
in: preposition
my band: the noun of the preposition