Oceanic trenches in combination with volcanic mountain systems lead to the formation of:

1. Troughs
2. Ridges
3. Fold mountains
4. Synclines

Volcanic activities are common in which of the following?

1. Young fold mountains
2. Old fold mountains
3. Residual mountains
4. Volcanic plateaus

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 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.