The correct option is B Pseudomonas
Xanthomonas is used for bioproduction of xanthan gum which is a polysaccharide and is used as a food additive. Bacillus thuringiensis (Bt) produces Bt toxin during sporulation. The toxin bind to receptors on midgut epithelial cells of gallworm, become inserted into the plasma membrane where they form pores leading to cell death through osmotic lysis; thus serving as biopesticide. Trichoderma serve as very effective biocontrolling agent for soil borne plant disease management. It is a free-living fungus, and reduces pathogenic infections by different mechanisms like competition, antibiosis, hyphal interactions, mycoparasitism, , and enzyme secretion. Pseudomonas putida is used in bioremediation owing to its aerobic metabolism with ability to degrade organic pollutants such as toluene and to convert styrene oil to biodegradable plastic Polyhydroxyalkanoates (PHA). Correct answer is A.