___________ is a type of carbonate sedimentary rock. It is mainly composed of the minerals calcite and aragonite.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. Limestone.
Limestone is a type of carbonate sedimentary rock that is mainly composed of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO₃).
Limestone is the most common carbonate rock and is typically formed from the accumulation and cementation of skeletal fragments of marine organisms like coral, mollusks, and foraminifera in clear, warm, shallow marine waters. A famous example of its use is the Great Pyramid of Giza. It is crucial for producing cement and lime (calcium oxide).
Other Options:
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Feldspar is a group of rock-forming tectosilicate minerals, which are igneous and metamorphic, not a sedimentary carbonate rock.
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Marble is a metamorphic rock, formed when the sedimentary rock limestone is subjected to intense heat and pressure, causing the original calcite and aragonite to recrystallize into an interlocking mosaic of coarser crystals.
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Garnet is a group of silicate minerals used as gemstones and abrasives, not a sedimentary rock.