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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] medium thorough-understanding
[mcq] Black soil develops deep cracks in summer due to its high clay content. Which of the following correctly explains why this property is considered agriculturally beneficial? (A) The cracks allow rainwater to percolate quickly, preventing waterlogging (B) The cracks aerate the soil and allow the soil to self-plough, mixing the lower and upper layers (C) The cracks reduce salinity by allowing salts to escape through the surface (D) The cracks increase the humus content by exposing the lower layers to sunlight
  1. A The cracks form because the soil lacks clay; they help drain excess water quickly.
  2. B The cracks form because the fine clayey soil shrinks on drying; they allow air to circulate and aerate the soil.
  3. C The cracks form because the soil is sandy; they help roots penetrate deeper.
  4. D The cracks form due to high phosphoric content; they increase the alkalinity of the soil.
Generated by claude-sonnet-4-6 · 2026-06-26 13:28 · grounding rag
Model Answer

Option B is correct. Black soil is made of extremely fine clayey material that shrinks on drying, developing deep cracks. These cracks allow proper aeration of the soil, making it agriculturally beneficial.

Source: Resources and Development, Classification of Soils – Black Soil

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Explanation

The textbook explicitly states: "They develop deep cracks during hot weather, which helps in the proper aeration of the soil." The key phrase is aeration, not drainage or salinity reduction. Option B in the MCQ choices also correctly identifies the cause (fine clayey soil shrinks on drying) alongside the benefit (aeration). Examiners expect students to link both the cause and the agricultural benefit accurately, ruling out options about sandy soil, phosphoric content, or salinity — none of which are mentioned in the context of black soil's cracking.

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