The correct option is B Agrobacterium mediated gene transfer
The picture depicts agrobacterium mediated gene transfer using leaf disc method. In leaf disc method for transformation, small discs are cut from leaf. This induces stress. Stressed leaf disc cells undergo dedifferentiation. Dedifferentiation makes the cells totipotent and with appropriate hormones they can grow into any other plant tissue. At this step, cells are infected with agrobacterium containing tamed Ti plasmid with the gene of interest. The desired gene gets integrated with plant genome. Cells are then allowed to redifferentiate into roots and shoots forming the transgenic plant.