Concept:Coastal erosion creates different landforms; when an arch collapses, the isolated column of rock left in the sea is called a stack.
Explanation:Waves attack a headland from both sides and gradually cut a cave through it, forming a natural arch.
With continued erosion, the roof of the arch weakens and eventually collapses.
The collapse leaves behind a tall, free-standing pillar of rock that is separated from the mainland.
This pillar, rising directly from the sea, is known as a stack.
If the stack is worn down further by waves, it may become a stump, which is submerged at high tide.
A headland is the original land mass projecting into the sea.
A tombolo is a ridge of sand or shingle that connects an island to the mainland.
A wave-cut platform is a flat rocky surface left behind as cliffs retreat.
Therefore, the only option that matches the description is a stack.
Answer:B. Stack