Assertion (A): External forces or Exogenic forces are Destructive Forces.

Reason (R): They produce relief such as mountains, plateaus, plains, lakes and big faults.

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.

Assertion (A): Residual mountains are also called mountains of denudation.

Reason (R): Denudation and erosion by natural agents cause mountains to be lowered.

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.

Mountains which are subjected to weathering and erosion for a long time are lowered down:

1. Old fold mountains
2. Volcanic plateaus
3. Relict mountains
4. Intermontane plateaus

Which of the following is/are correctly matched?

1. Young fold mountains: Himalayas, Alps
2. Old fold mountains : Urals, Aravalli
3. Residual mountains : Nilgiri, Rajmahal Hills
4. All of the above.