Which large-scale geoscience processes are responsible for the decrease in height of Mt. Mitchell? weathering and erosion, plate tectonics and seafloor spreading , or deposition and valley carving?

weathering and erosion

Explanation:

Weathering and erosion are the main causes of the decrease in the height of Mount Mitchell, since these are the two main processes that result in dispersion and a decrease in the amount of land "mass". Weathering is the natural process of decomposition of the rock, while erosion is the process of removal of rocks or terrestrial material, which is lost due to wind, rain, among other factors.