Arrange the following species of trees in a sequential order from foot-hills to higher altitudes of Himalayas.
1. Alpine Pastures.
2. Needle forest.
3. Temperate deciduous forest.
4. Sub-tropical forest.
1
4, 3, 2 and 1
2
4, 3, 1 and 2
3
3, 4, 1 and 2
4
1, 2, 3 and 4