The disintegration of rocks by atmospheric agents at or near the surface of the earth:

1. Erosion
2. Weathering
3. Mass movement
4. Denudation

The displacement of rocks by agents like wind, water or ice:

1. Deposition
2. Transportation
3. Erosion
4. Mass wasting

Assertion (A): In the upper course the dominant activity of a river is erosion.

Reason (R): The river flows swiftly as the gradient is steep.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.

The laying down of material that has been weathered, eroded and transported by natural processes such as water, wind and ice.

1. Physical Weathering
2. Deposition
3. Denudation
4. Tributary