10
 Set a melody to words  -
I don’t suppose there’s any correct or incorrect choice of voice, although a “machismo”
    text might suggest an adult male voice, while a more “feminine” text, a female voice.
     But given their can be no accusations of sexist bias and the texts are generally
    gender neutral, I would pick a voice to suit a clef you are most comfortable working
    in:-
i.e. “pick” a soprano voice if you want to work in the treble clef, a baritone voice for the bass clef.
I write “pick” in quotes because you never explicitly state the voice you are writing
    for (unless you include it as a “performance direction”, which I would recommend)
    -
So whatever voice you “pick”, you must work within its pitch range -