The correct option is D Overgrazing
After the imposition of restrictions, the pastoralists had to feed their herds with whatever pasture they could find within a specific area. This led to continuous and intensive grazing in one area. Such lands were overgrazed leading to decline in pasture quality. As a result, there was a serious shortage of forage for animals. Due to this, animal stock deteriorated and large numbers of underfed cattle died due to scarcities and in famines.