Generally speaking, the meaning of farming refers to the mechanical operation of the soil in order to improve the growth conditions of the crops before planting or during the growth period.There are three purposes of farming:(1) to improve the structure of the soil; (2) to bury and blend crop residues and organic manure into the soil;  (3) to remove weeds and other unwanted plants.
According to the above definition, which of the following is farming?
Spray insecticide to kill pests.