Read the sentence. When the Spaniards decided to conquer Mexico they appointed Hernan Cortes to lead the army. Which answer shows proper comma usage? When the Spaniards, decided to conquer Mexico, they appointed Hernan Cortes to lead the army. When the Spaniards decided to conquer Mexico they appointed Hernan Cortes, to lead the army. When the Spaniards decided to conquer Mexico, they appointed Hernan Cortes to lead the army. When the Spaniards decided, to conquer Mexico, they appointed Hernan Cortes to lead the army.