Escuchar

Question

Escuchar means "to listen to", rather than "to listen" I thought.  That's why I chose "quienes" rather than "a quienes" (plus the accents!).  But you have to include the "a" in this case, do you?  I know the Spanish like to duplicate prepositions!!

Answer

Hola Alan,
I imagine you are referring to this question: 
¿___ debemos escuchar? (Whom do we have to listen to?)
A quiénes
When you listen to something, for example, "Escucho la radio todos los días" (I listen to the radio everyday) you don't need "a", but when you listen to someone/people, it is "escuchar a...". In this case we are referring to people, in the form of a question, therefore you need "a", ¿A quiénes debemos escuchar?
I hope this clarified your doubt.
Un saludo