The correct answer is option 1: Sand spit.

A long narrow stretch of sand and/or shingle with one end attached to the mainland is called a sand spit. A sand spit is formed by the process of longshore drift, which is the movement of sediment along the coast. As waves approach the shore at an angle, they carry sand and sediment along the coast. When this sediment encounters a change in the shoreline, such as a river mouth or a change in the direction of the coastline, it can accumulate and form a sand spit.

A sand spit typically has one end attached to the mainland, while the other end extends out into the water. It is often curved or hooked in shape. Sand spits are commonly found at the mouths of rivers or at coastal bends.

Option 2, sand bar, refers to a submerged or partially exposed sandbank found in a body of water such as a river or ocean. Option 3, sand dune, refers to a hill or mound of sand formed by wind and/or water erosion. Option 4, tombolo, refers to a sandy bridge connecting an island to the mainland or another island.

Alert - correct answer should be option 4: Tombolo. A long narrow stretch of sand and/or shingle with one