The correct option is B Bacillus thuringiensis
Bacillus thuringiensis (abbreviated as Bt) is the name of a bacterium which produces a toxin which kills pests on plants and crops. Hence, the bacterium is used as a biopesticide. In transgenic crop plants, the toxin-producing gene was seperated from the bacterium and transferred into the crop plants so as to make the crop pest resistant. The toxin-producing gene inserted into the plant's genome produces toxin crystals that the plant would not normally produce which dissolves the gut lining of the pest, leading to the organism's death, when ingested by a population of pests. Example: Bt cotton