Batholiths and sills are both intrusive volcanic features. Volcanism helps to produce igneous rock hence C is the best answer.

Carbonation (A) is a form of chemical weathering involved with limestone rock. It is also known as solution.

River deposition (B) would produce features such as deltas, levees, or alluvial soil.

Extensive wind erosion was a major problem on the prairies of North America during the Great Depression of the 1930s resulting in Dust Bowl conditions.