The lowering of land, rounding of exposed rock surfaces and levelling of the peaks:

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

Assertion (A): In the lower course of the river all the ideal conditions for depositional landforms exist.

Reason (R): The load-transporting capacity is drastically reduced due to sluggish flow as well as division of a river into many distributaries.

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.

How do migratory dunes damage towns and villages?

1. They cover all surfaces with thick layers of sand.
2. The large mass of sand shifts further.
3. They can be checked by building walls.
4. All of the above.

Assertion (A): Barchan are moon-shaped live dunes.

Reason (R): The migration of the barchans is a threat to desert life.

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.