Final answer:
Philip's greatness as a military leader is portrayed by listing examples of his victories over other armies (option b).
Step-by-step explanation:
Alexander develops the idea that Philip was a great military leader by listing examples of Philip's victories over other armies. Philip was a tactical innovator, organizing his nobles into elite cavalry units and successfully leading his troops into battle.
He also reorganized the infantry into a new kind of phalanx and used a combination of this new phalanx and his cavalry to achieve unstoppable success. Philip's conquests and success in battle demonstrate his greatness as a military leader.