The correct option is B Stem (rhizome)
Vegetative propagation is defined as the production of new plants from the vegetative plant parts like leaf, stem, roots of the parent plant. In ginger, the vegetative propagation occurs through the underground stem called rhizome. A rhizome is an underground horizontal stem, with stored foods and buds. Manufactured foods are transported down to enable the growth of the rhizome. The lower portion of the rhizome develops roots and helps in the conduction of water and minerals.
Thus, the correct answer is option (B), 'Stem (rhizome)'.