The sharp pillars hanging from the roof of a cavern in limestone regions are called

Step 1: Analyze the question The question asks for the name of the pointed pillars that hang from the roof of a cavern in limestone (karst) regions.

Step 2: Explain the concept When rainwater absorbs carbon dioxide, it becomes weak carbonic acid. This acid dissolves limestone (calcium carbonate) and forms caves underground. Inside the caves, water drips from the roof. As it drips, it loses some carbon dioxide and deposits calcite, which builds up slowly into formations.

• Stalactites form on the roof and grow downward.
• Stalagmites form on the floor and grow upward.
• When the two meet, they form a pillar or column.

Step 3: Go through the options

• A. Dolines: These are circular depressions or sinkholes on the surface of limestone areas. They are not found hanging in caverns.
• B. Stalagmites: These rise from the cave floor. This is the opposite of what the question describes.
• C. Uvalas: These are large depressions formed when several dolines join together. They are surface features.
• D. Stalactites: These hang from the cave roof like icicles. This matches the question.

Step 4: Answer The correct answer is **D.

Step 5: Exam tip Use this memory trick:

• Stalactites hold tight to the ceiling.
• Stalagmites might reach the ceiling from the ground.

You can also remember that c stands for ceiling and g stands for ground.