Your answer is B., to avenge Patroclus, because he didn't want to fight in da battle because of King Agememnon's selfish greediness, but since the Trojans killed his most beloved friend, he went to fight in da war to get back revenge. ;-)
If you are taking da Unit Assessment on this, I will give you da answers as I have mastered it. ;-)
I hope I helped! =D