Choose the correctly matched cave feature and its formation:

Correct — B. A stalagmite rises from the cave floor, but the water that builds it comes from above. Water carrying dissolved calcium carbonate drips from the ceiling, usually after running down a stalactite, and deposits the mineral where it lands.

So option (b) pairs the stalagmite with its real source: ceiling drippings, building upward from the floor.

Why the others are wrong

• (a)
  Stalactite – Grows upward from cave floor — That describes a stalagmite, not a stalactite. Stalactites hang down from the ceiling; the stalagmite is the one that grows upward from the floor.
• (c)
  Pillar – Hangs from the cave roof — A pillar, or column, forms when a stalactite and a stalagmite grow until they join, so it links floor and roof rather than hanging from the roof.
• (d)
  Stalactite – Formed by upward mineral flow — A stalactite grows downward from the ceiling, deposited by water seeping and dripping from above, not by an upward flow of minerals.

Limestone caves are karst landforms. Rainwater carrying dissolved carbon dioxide dissolves limestone and carries calcium carbonate underground.

When that water drips into a cave, it leaves the calcium carbonate behind. Stalactites hang from the ceiling, stalagmites rise from the floor below them, and the two can fuse into a column or pillar.

Key facts

• Stalactites hang from the cave ceiling, and stalagmites rise from the floor beneath them.
• Both are deposits of calcium carbonate left by dripping, mineral-rich water.
• A column forms when a stalactite and a stalagmite grow long enough to join.

Common traps

• Rejecting option (b) because a stalagmite grows from the floor, when the dripping water that builds it still comes from the ceiling.
• Swapping the two names: the c in stalactite goes with ceiling.

No directly related past PYQ was found.