Concept: Mining activities that destroy vegetation and poison the soil permanently reduce the quality of the land.Explanation:Earth moving machines remove the top layer of soil and destroy the vegetation cover. Chemicals like cyanide and mercury enter the soil and make it toxic for future use. Removing 60 acres of vegetation every hour leaves the land bare, exposed, and unproductive. This long-term damage to the land's condition is called land degradation. Erosion is only one possible result, but degradation includes the entire harmful effect of mining on the land.Answer:A. Degradation