The correct answer is (a) Igneous rocks.
Igneous rocks are formed when magma or lava cools and solidifies. They are the most common type of rock on Earth, and they make up the majority of the planet’s crust. Igneous rocks can be classified into two main types: intrusive and extrusive. Intrusive igneous rocks form when magma cools and solidifies beneath the Earth’s surface. Extrusive igneous rocks form when lava cools and solidifies on the Earth’s surface.
Red soils are formed when igneous rocks weather. The weathering process is caused by the action of water, wind, and ice. These agents break down the rocks into smaller pieces, which are then transported away by erosion. The red color of red soils is due to the presence of iron oxide. Iron oxide is a common mineral that is found in igneous rocks. When the rocks weather, the iron oxide is released and forms a red pigment.
The other options are incorrect because they are not the main type of rock that forms red soils. Sedimentary rocks are formed when sediments, such as sand, silt, and clay, are deposited and compacted. Metamorphic rocks are formed when existing rocks are subjected to heat and pressure. Volcanic rocks are formed when lava erupts from a volcano.
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