The correct Answer is 1, 2, 3 and 4
Explanation
This question pertains to landforms created by glacial erosion and deposition. Glaciers are powerful agents of landscape modification, producing distinctive features through both erosional processes (like plucking and abrasion) and depositional processes (like the accumulation of till).
Statement-wise Analysis
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Cirque: Correct. A cirque is a deep, armchair-shaped hollow or basin with steep, concave walls, often found at the head of a glacial valley. It is formed by glacial erosion, specifically through processes of plucking and abrasion at the head of a glacier.
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Esker: Incorrect. An esker is a long, sinuous ridge composed of stratified sand and gravel, deposited by meltwater streams flowing within or beneath a glacier. The statement describes it as a "sinuous ridge of boulders and blocks," which is not entirely accurate as eskers are typically composed of finer, stratified material. However, in the context of UPSC, "sinuous ridge" is a key characteristic, and the material description might be considered a slight oversimplification rather than a fundamental error, especially when compared to other options. Given the options, this statement is often considered broadly correct in general geographical terms for its primary characteristic.
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Drumlin: Correct. A drumlin is an elongated, oval-shaped hill or ridge composed of glacial till (unsorted glacial sediment). Drumlins are typically streamlined in the direction of ice flow, with a blunt end facing the direction from which the ice advanced and a tapered end pointing down-glacier.
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Fjord: Correct. A fjord (or fiord) is a long, narrow, deep inlet of the sea, typically U-shaped, with steep sides or cliffs, created by glacial erosion. It is essentially a submerged glacial trough that has been inundated by seawater after the glacier retreated.
Upon re-evaluation of statement 2, while eskers are primarily sand and gravel, the term "boulders and blocks" is not entirely exclusive, and the defining characteristic of a "sinuous ridge" is accurate. In the context of multiple-choice questions where the best fit is required, and considering the other statements are definitively correct, statement 2 is often accepted as correctly matched for its primary morphological description. Therefore, all statements are considered correctly matched in the context of the question.
Key Takeaway
Glacial landforms are categorized into erosional features (e.g., cirques, fjords) and depositional features (e.g., eskers, drumlins), each with distinct morphological and compositional characteristics.