Escribe la frase con el pronombre que reemplaza el OBJETO INDIRECTO.
Rewrite the entire sentence replacing the indirect object with an indirect object pronoun.
La maestra da un examen a ustedes.
Answer : La maestra les da un examen.
Explanation : The indirect object is a plural noun, then the indirect object pronoun, have to be plural too . "Les" replaces "a ustedes"
Hope this helps!