Which of the following sequence is correct in the formation of a stack

Analyze the question: You are asked for the correct order of landforms that leads to the formation of a sea stack through coastal erosion.

Explain the concept: Stacks form on rugged coastlines where waves attack a headland (a piece of land jutting into the sea). Wave action works through:

• Hydraulic action: the force of water pounding into cracks.
• Abrasion (corrasion): rocks hurled by waves wear the cliff away.

Step-by-step solution:

1. Headland: Resistant rock juts out into the sea, and waves concentrate their energy on it.
2. Cave: Waves attack weaknesses (cracks and joints) in the headland and enlarge them into a cave.
3. Arch: The cave deepens until it cuts through the headland, leaving an opening with rock above it, which is an arch.
4. Stack: Continued erosion weakens the arch's roof until it collapses, leaving an isolated pillar of rock standing in the sea, which is a stack.

The sequence is: Headland → Cave → Arch → Stack

Checking the options:

• A: Starts with a cave, so it leaves out the headland as the starting point. Wrong.
• B: Headland, cave, arch, stack. Correct (the comma is missing after "headland" in the printed option, but the order is right).
• C: Puts the arch before the cave, which is impossible. Wrong.
• D: Puts the cave before the headland. Wrong.

Tip: Remember "H-C-A-S", as in "How Can Add Sugar?" Headland, Cave, Arch, Stack. After a stack collapses further, it becomes a stump.