In physical geography, ___________ is the wearing away and gradual removal of the Earth's landscape by different external agents such as running water, moving wind, and flowing ice (glaciers).

Introduction / Context:
Erosion is a key concept in physical geography and Earth science. It explains how landscapes gradually change shape as material is worn away and transported by natural agents. Understanding erosion helps students interpret landforms such as valleys, canyons, river banks, coastal cliffs, and glacial features. This question checks whether you can distinguish erosion from related processes like weathering, attrition, and abrasion, which are often mentioned together but do not all mean the same thing.

Given Data / Assumptions:
- The question refers to wearing away of the landscape, meaning removal of surface material over time.
- It specifically mentions different agents: water, wind, and ice.
- The options include several geomorphological terms: weathering, attrition, erosion, and abrasion.
- We assume standard geography definitions used in school and competitive examinations.

Concept / Approach:
In geography, erosion is defined as the wearing away and removal of rock and soil from one place to another by moving agents such as rivers, sea waves, wind, and glaciers. Weathering, by contrast, is the in situ breakdown or disintegration of rocks at or near the Earth's surface without significant movement of the material. Attrition and abrasion are more specific sub processes that describe how particles collide or scrape during transport. Because the question clearly stresses both wearing away and the action of agents like water, wind, and ice, the most accurate and complete term is erosion.

Step-by-Step Solution:
Step 1: Focus on the phrase “wearing away of the landscape” and note that material is being removed over time. Step 2: Observe that the question lists agents such as water, wind, and ice, which are the classic erosional agents. Step 3: Recall that erosion involves both the wearing away and the transportation of rock and soil by these moving agents. Step 4: Differentiate this from weathering, which is only the breakdown of rocks in place without major movement. Step 5: Conclude that the term matching the description in the question is erosion.

Verification / Alternative check:
Textbooks usually define erosion as “the wearing away of the landscape by different agents of gradation such as running water, wind, and moving ice.” Diagrams of river erosion, coastal erosion, and glacial erosion all show material being removed and carried away, not just cracked or broken. Weathering chapters emphasise processes like temperature changes, chemical reactions, and biological activity that weaken rocks in place. This clear separation confirms that erosion is the correct term for landscape wearing and removal by moving agents.

Why Other Options Are Wrong:
Weathering, the breakdown of rocks in place without major movement, does not necessarily involve transportation of material by water, wind, or ice.
Attrition, the knocking of rock fragments against each other, is a specific erosional process within rivers and waves, not the overall name for landscape wearing.
Abrasion, the scraping and grinding of rock surfaces by transported material, is again a particular mechanism, not the broad concept covering all agents and all removal of material.

Common Pitfalls:
Many students confuse weathering and erosion, using the words as if they were synonyms. A simple way to remember the difference is: “weathering breaks it, erosion takes it.” Weathering weakens and breaks rocks in place, while erosion actually carries the material away. Attrition and abrasion are sub types of erosion, not replacements for the main term. Recognising this hierarchy of terms helps you choose erosion confidently in questions that mention the wearing away of the landscape by agents like water, wind, and ice.

Final Answer:
The wearing away of the landscape by different agents like water, wind, and ice is called Erosion, the wearing away and removal of rock and soil by agents like water, wind, and ice.