Hint: Laterization is a type of the weathering process through which rock is converted to laterite. It develops a huge variety in grade, thickness, chemistry, and ore mineralogy of the resulting product. Laterization is also known as tropical weathering. It includes chemical and physicochemical changes.
Complete answer: Laterization is a pedogenic process (soil formation) found in tropical and subtropical environments. It involves chemical and physicochemical changes and conversion of primary rock-forming minerals into compounds rich in lattice clay minerals and laterite constituents. It involves three steps: i. The first step is decomposition which involves the breakdown of minerals resulting in the release of constituent elements like calcium oxide, magnesium oxide, etc. ii. The second step is laterization which involves leaching (loss of soluble substances and colloids from the topmost layer of soil). iii. The third step involves dehydration or desiccation of minerals. Also, soil degradation or retrogression is the decline in the soil condition caused due to improper use or poor management. Purification of water involves the removal of contaminants and the methods used are sedimentation, filtration, etc. Soil sterilization is a chemical or physical process that involves the death of organisms present in the soil. Hence, the correct answer is option C, i.e., formation of soil.
Note: Laterization is a type of weathering process which involves the breakdown of rock particles into the soil by involving various chemical and physicochemical changes. This whole process mainly takes place in three major steps of decomposition, laterization, and dehydration or desiccation.