Question

a peninsula is a piece of land that is surrounded by
unfriendly countries. friendly countries. water on three sides.
water on all sides.

Explanation:

The definition of a peninsula is a landform that is surrounded by water on three sides while still being connected to the mainland. A landform surrounded by water on all sides is an island. The options about countries (friendly or unfriendly) are not related to the geographical definition of a peninsula.

Answer:

water on three sides.