This map shows Macedonia and the Greek city-states.

A map titled Macedonia. A key shows Macedonia and Greek city-states by color. The shaded areas are bordered by the Aegean Sea, Ionian Sea, and Mediterranean Sea.

Why did Philip II need a navy to defeat the Greek city-states?

The city-states were surrounded by water.
Most city-states were located on islands.
Most city-states were located across the Aegean Sea.
The city-states had allies near the Mediterranean Sea.