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Social Science (087) — AI-generated practice question

AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.

Q1. [1] straightforward exam-ready
Bauxite, from which aluminium is extracted, is formed by which of the following processes? (A) Cooling of molten magma in veins and lodes (B) Evaporation in arid regions (C) Decomposition of surface rocks leaving a residual weathered mass (D) Deposition in horizontal sedimentary strata
  1. A Cooling of molten magma in veins and lodes
  2. B Evaporation in arid regions
  3. C Decomposition of surface rocks leaving a residual weathered mass
  4. D Deposition in horizontal sedimentary strata
Generated by claude-sonnet-4-6 · 2026-06-26 13:32 · grounding rag
Model Answer

(C) Decomposition of surface rocks leaving a residual weathered mass

Bauxite is formed by the decomposition of surface rocks and removal of soluble constituents, leaving a residual mass of weathered material.

Source: Chapter 5, Mode of Occurrence of Minerals

Explanation

The textbook explicitly states: "Another mode of formation involves the decomposition of surface rocks, and the removal of soluble constituents, leaving a residual mass of weathered material containing ores. Bauxite is formed this way." This is also directly tested in Exercise Q1(i). Options A, B, and D describe formation of metallic minerals in igneous rocks, evaporite minerals (like gypsum), and sedimentary minerals respectively — not bauxite.

Previous-year CBSE Grade 10 board exam questions, organised by subject and chapter, each with a model answer — free to read and print.