The correct option is B Both 1 and 2
The process of large-scale cutting down of trees in a forest area is called deforestation.
Deforestation has numerous adverse effects like:
(i) The loss of trees affects the water balance, which causes changes in the global average temperature (global warming).
(ii) Clearing of forest area results in the loss of habitat of animals.
(iii) The loss of trees makes the area easily susceptible to soil erosion, which results in the desertification of the forest area.