What is a tombolo?

A tombolo is defined as a sand bar or accumulation of sediment that connects an island to the mainland. This geological feature typically forms due to the actions of waves and currents, which deposit materials in such a way that land is created, effectively linking the island to the adjacent coastline. The formation of a tombolo can be influenced by various factors, such as the direction of prevailing winds and the patterns of wave action, which can concentrate sediment deposition in specific areas.

This makes the correct answer particularly significant as it highlights the dynamic relationship between coastal processes and landforms. Understanding tombolos is critical because they can affect local ecosystems, coastal navigation, and human activities such as tourism and fishing. Other options do not accurately describe a tombolo, as they pertain to different geological processes and formations.