Answer:
Peninsulas have a lot of coastline.
Explanation:
Island is a type of land that lies in the middle of the water, meaning being completely surrounded by it.
Forest is a land that is covered with all sorts of trees, plants, and other undergrowth. Forests widely appear on both island and peninsula.
Desert is a type of land that is inhabited and mostly consists of sand, and it is not a must that they are located on some peninsula.
As said in the question, the peninsula is surrounded by water on three sides, which makes it have a long coastline, which is also the answer to the question asked.
