Twirling her wand Arya listened to the answers that were given in class and then thought long and hard about Truebridge's question. To her the question seemed extreamly vauge, like he wanted you to be creative or something, which was why she was slightly hesitant to answer.

After another long moment, she hesitantly rose her hand. "Do you just mean spells that were like....invented for the purpose of defense or spells that could be used defensively?" She mused, vaguely remembering the last lesson she had with the professor. "Cause if its the former then spells like Finite, Protego, or the Fidelius Charm are some. But if its the latter then a lot of spells could be used defensively I think. Immobulus or Impedimenta could be used to stop a spell or object. You could use a Conjuring spell to conjure object to use for defense. Muffliato....could be used defensively in a duel. Kinda like an element of surprise thing, so if your opponent can't hear you then you have a greater chance of winning the duel?" Maybe? Arya lowerd her hand with a slightly quizzical expression, still musing over her answer, unsure if she had gotten her point across. Looking around her, she picked up her notebok and jotted down some notes.