Name the plateaus, formed along with fold mountains, that are surrounded by hills and mountains on all sides.

1. Volcanic Plateaus
2. Structural Plateaus
3. Intermontane Plateaus
4. Depositional Plateaus

Assertion (A): Many lakes exist in the vast lowland of the Great Plains of the USA.

Reason (R): The Great Plains were formed due to uplift of land submerged under water.

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.

Why are the fold mountains called so?

Give two chief characteristics of the fold mountains.