When the troughs of tributary glaciers lie above sea level, these hanging valleys can create?

Fjord -  A fjord or fiord is a steep water inlet which is narrow. It is created due to glacial erosion. Long ago, when the earth was covered with glaciers, they cut bedrock into U-shaped valleys. As the glaciers moved, they would leave a narrow waterway in their path, due to melting. These waterways are called fjords.

My answer is letter d

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