According to a latest research, Pakistan is predominantly a dryland country; 80% of its land area is arid and semi arid, 12% sub-humid and 8% under humid climate. Thus , soils of arid & semi-arid regions are vulnerable to a wide range of degradation process. As the case in arid and semi-arid climates elsewhere in south-central/southern Asia and Sub-Saharan Africa; _________________ are among the major causes of soil degradation and desertification?
A. Drought stress
B. Accelerated erosion & salinization
C. Depletion of soil fertility and SOM
D. All of the above