The correct Answer is A-4, B-2, C-1, D-3
Explanation
The Earth's interior is structured into several concentric layers, each characterized by distinct physical and chemical properties. Discontinuities mark the boundaries between these layers, while specific layers exhibit unique compositions and states.
Statement-wise Analysis
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A. Moho's discontinuity - 4. Boundary between crust and mantle
Correct: The Mohorovičić discontinuity, commonly known as Moho's discontinuity, represents the boundary separating the Earth's crust from the underlying mantle. It is characterized by a significant increase in seismic wave velocity.
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B. Asthenosphere - 2. Upper portion of mantle, source of magma
Correct: The asthenosphere is a highly viscous, mechanically weak, and ductile region of the upper mantle. It lies beneath the lithosphere and is characterized by partial melting, making it the primary source of magma that erupts at volcanoes.
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C. Lithosphere - 1. Crust and uppermost mantle
Correct: The lithosphere is the rigid outermost shell of a terrestrial-type planet or natural satellite. On Earth, it comprises the crust and the uppermost solid part of the mantle. It is broken into tectonic plates.
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D. Nife layer - 3. Core made of nickel and iron
Correct: The term 'Nife' is an abbreviation derived from the chemical symbols for Nickel (Ni) and Iron (Fe). This term is historically used to refer to the Earth's core, which is predominantly composed of these two elements.
Key Takeaway
The Earth's internal structure consists of distinct layers and boundaries, including the lithosphere (crust and uppermost mantle), asthenosphere (upper mantle, magma source), Moho's discontinuity (crust-mantle boundary), and the Nife layer (core, primarily nickel and iron).