The correct answer is Agrobacterium tumefaciens. Agrobacterium tumefaciensAgrobacterium tumefaciens has extensive usage in genetic engineering work in plants. It is a soil-borne, plant pathogenic bacterium that causes tumorous growths. It has the ability to transfer a particular type of DNA segment (T-DNA). It induces the tumour-inducing plasmid (Ti) into the infected cells. It is integrated into the host genome and transcribed, causing the crown gall disease. Additional InformationClostridium septicumIt is a gram-positive, rod-shaped bacterium. It is a spore-forming, obligate anaerobic bacteria. It is one of several bacteria responsible for myonecrosis or gas gangrene. It is associated with malignancy. Xanthomonas citriIt is a gram-negative, rod-shaped proteobacterium. It is a phytopathogen that is harmless for humans. Phytopathogen is the causing agent of citrus canker, a disease that affects citrus fruits. Bacillus coagulensIt is an endospore that produces lactic acid. It forms soil bacteria that are used as probiotics. It is similar to lactobacillus.