How Did the Nature of Warfare Change Under the Hellenistic

How did the nature of warfare change under the Hellenistic empires?

A) Warfare was no longer confined to the battlefield; now cities were attacked directly and whole populations threatened.
B) Warfare became subject to sets of laws meant to limit damage to property and to civilian populations.
C) Warfare was established as the principal occupation of states, with other duties such as religious rites and civil order of much less significance.
D) Hellenistic empires sought to resolve disputes through diplomacy, establishing the principle that warfare was an act of last resort.