The correct answer is C. Hybridization is the cross-fertilization between two varieties of the same species. This can be done by hand or by using a machine. Hybridization can be used to create new varieties of plants with desirable traits, such as disease resistance or higher yields.
A. Decayed vegetable matter is called humus. It is a dark, organic material that forms in the soil when plants and animals die. Humus helps to improve the soil’s structure and fertility.
B. Tilling the land is the process of breaking up the soil with a plow or other implement. This is done to prepare the soil for planting. Tilling can also help to control weeds and pests.
D. Downward movement of water through soil is called infiltration. This is an important process in the water cycle. Infiltration helps to replenish groundwater supplies and to prevent flooding.