Which coastlines have low wave energy and are surrounded by land masses?

• A. Open coasts
• B. Collision coasts
• C. Trailing-edge coasts
• D. Marginal sea coasts

Answer: (D)

Wave energy at a shoreline is largely controlled by how exposed the coast is to open ocean swells and how far winds can blow over water (fetch). When a coast is sheltered by land and lies behind a nearly enclosed sea, the fetch is short and waves don’t grow very large. This keeps wave energy low.

A marginal sea is a sea that is partially enclosed by land and connected to a larger ocean by narrow passages. Because it’s largely surrounded by land, waves entering the coast from the open ocean are diminished, leading to calmer shorelines with low wave energy.

So coastlines along marginal seas fit the description best: they’re surrounded by land masses and experience lower wave energy than open-ocean coasts.