Destruction of tundra vegetation will likely result in a. deepening of the active zone b. lessening of soil moisture c. freezing of the soil d. melting of the permafrost

I think the correct answer from the choices listed above is option D. Destruction of tundra vegetation will likely result in melting of the permafrost. The tundra ecosystem is extremely sensitive to disturbance with little ability to restore itself. The melting of the permafrost will cause the collapse of ground and loss of soil.