Question

Which one is an example of Sedimentary Rock?
(A) Sandstone
(B) Granite
(C) Marble
(D) Basalt

Answer 1

Hint: Rocks are very abundantly available since they are formed by the Earth and so they form a significant portion of our planet's surface. Igneous, sedimentary, and metamorphic rocks are the three main categories in which rocks can be classified. Sedimentary rocks are made up of different rocks' deteriorated remnants or even by the remnants of plants and animals.

Complete answer:
Sedimentary rocks develop from already occurring minerals or fragments of creatures that used to be alive. They emerge as a result of deposits accumulating on the surface of the Earth. Bedding or layering in sedimentary rocks is common.
This form of rocks is frequently formed from sediments transported by rivers and accumulated in bigger water bodies like lakes and oceans. As sediments are buried, they absorb heat and result in loss of water and become solidified together to form rock.

Let us look into the given options:
Option (A) Sandstone is the correct option. Sandstone is indeed a sedimentary rock that is often made up of sand-sized minerals and particles of rocks. Sandstone is a kind of sedimentary rock that is very widespread. Sand deposits are transported to the basin by rivers to form sandstones.
Option (B) Granite is an incorrect option. Granite is by far the most abundant plutonic rock present on the Earth's crust, they contain feldspar and quartz and they are a type of igneous rocks. They are formed due to magma cooling down(silicate melt) deep under the surface of the earth. Since they are igneous they are not sedimentary.
Option (C) Marble is an incorrect option. When rocks that were originally limestone rocks are heated to very high temperatures in such a way that the particles of the mineral expand and bind together, marble emerges. They are made of a certain existing rock so they are metamorphic rocks. Being metamorphic, they cannot be called sedimentary rocks.
Option (D) Basalt is an incorrect option. Basalt is classified as a mafic, igneous, volcanic rocks formed by the flow of lava in many different volcanoes. Since basalt is mafic, it contains minerals that are high in iron and magnesium. Since they are a type of igneous rocks, it is not sedimentary.

Thus the correct answer is option ‘A’.

Note: When readily formed sedimentary or igneous rocks are altered by heat, forces, pressure or reactive substances such as hot water with other minerals, metamorphic rocks get formed. The majority of rocks are composed of silicon and oxygen-containing minerals, where silicon and oxygen are the two most common resources in the Earth's crust.