With reference to the work of wind, consider the following statements: 1. Mushroom rocks are commonly found in river valleys. 2. Winds erode the lower section of the rock more than the upper part. 3. Sand dunes are low hill-like structures formed by wind deposition. Which of the statements given above is/are correct?

Correct Option The correct option is (c) 2 and 3 only. Explanation Wind acts as a prominent geomorphic agent in arid and semi-arid regions (deserts). It shapes the landscape through two primary processes: erosion (abrasion and deflation) and deposition (accumulation of transported materials). Statement-wise Analysis - Statement 1 is Incorrect: Mushroom rocks are characteristic landforms found in deserts, not river valleys. They are created by the mechanical weathering and abrasion caused by wind. River valleys are landforms associated with the erosional work of running water. - Statement 2 is Correct: Winds transport sand and dust particles. The concentration of coarser and heavier sand grains is significantly higher near the ground surface. As a result, the abrasive action of the wind is most effective at the base of rock formations. This leads to the lower section of the rock being eroded more than the upper part, creating a structure with a narrow base and a broad top, resembling a mushroom. - Statement 3 is Correct: Sand dunes are depositional landforms. When the wind velocity drops or the wind encounters an obstacle (such as a rock or vegetation), it drops its load of sand. These accumulations form low hill-like structures known as sand dunes. Key Takeaway: Mushroom rocks are products of differential wind erosion (undercutting), while sand dunes are products of wind deposition in desert environments.

NCERT Class 7 Geography — Chapter 2: Our Changing Earth

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With reference to the work of wind, consider the following statements:

Mushroom rocks are commonly found in river valleys.
Winds erode the lower section of the rock more than the upper part.
Sand dunes are low hill-like structures formed by wind deposition.

Which of the statements given above is/are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

Correct Option

The correct option is (c) 2 and 3 only.

Explanation

Wind acts as a prominent geomorphic agent in arid and semi-arid regions (deserts). It shapes the landscape through two primary processes: erosion (abrasion and deflation) and deposition (accumulation of transported materials).

Statement-wise Analysis

Statement 1 is Incorrect: Mushroom rocks are characteristic landforms found in deserts, not river valleys. They are created by the mechanical weathering and abrasion caused by wind. River valleys are landforms associated with the erosional work of running water.
Statement 2 is Correct: Winds transport sand and dust particles. The concentration of coarser and heavier sand grains is significantly higher near the ground surface. As a result, the abrasive action of the wind is most effective at the base of rock formations. This leads to the lower section of the rock being eroded more than the upper part, creating a structure with a narrow base and a broad top, resembling a mushroom.
Statement 3 is Correct: Sand dunes are depositional landforms. When the wind velocity drops or the wind encounters an obstacle (such as a rock or vegetation), it drops its load of sand. These accumulations form low hill-like structures known as sand dunes.

Key Takeaway: Mushroom rocks are products of differential wind erosion (undercutting), while sand dunes are products of wind deposition in desert environments.

Your note

More from Chapter 2: Our Changing Earth

Consider the following statements regarding the Lithospheric plates: 1. They move around very slowly, just a few millimetres each year. 2. Their movement is driven by the rotation of the earth on its axis. 3. The molten magma inside the earth moves in a circular manner. Which of the statements given above is/are correct?

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With reference to Earth movements, consider the following statements: 1. Endogenic forces work on the surface of the earth. 2. Diastrophic forces are a type of Endogenic force. 3. Sudden forces can cause mass destruction over the surface of the earth. Which of the statements given above is/are correct?

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Consider the following statements regarding the evolution of landforms: 1. Building mountains is an effect of Diastrophic forces. 2. Glaciers and Sea-waves are agents of Endogenic forces. Which of the statements given above is/are correct?

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The lithosphere is broken into a number of plates known as:

easy

What causes the movement of Lithospheric plates?

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Keep practising Chapter 2: Our Changing Earth

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Correct Option

The correct option is (c) 2 and 3 only.

Explanation

Statement-wise Analysis

Statement 1 is Incorrect: Mushroom rocks are characteristic landforms found in deserts, not river valleys. They are created by the mechanical weathering and abrasion caused by wind. River valleys are landforms associated with the erosional work of running water.
Statement 2 is Correct: Winds transport sand and dust particles. The concentration of coarser and heavier sand grains is significantly higher near the ground surface. As a result, the abrasive action of the wind is most effective at the base of rock formations. This leads to the lower section of the rock being eroded more than the upper part, creating a structure with a narrow base and a broad top, resembling a mushroom.
Statement 3 is Correct: Sand dunes are depositional landforms. When the wind velocity drops or the wind encounters an obstacle (such as a rock or vegetation), it drops its load of sand. These accumulations form low hill-like structures known as sand dunes.

Key Takeaway: Mushroom rocks are products of differential wind erosion (undercutting), while sand dunes are products of wind deposition in desert environments.