Concept:Ginger is a stem-modified plant that grows from an underground storage stem.Explanation:Ginger does not reproduce mainly through seeds, suckers, or corms.Its underground stem is swollen and fleshy, which stores food.This modified stem is called a rhizome.When planted, buds on the rhizome grow into new ginger plants.Therefore, the common method of propagation is by using the rhizome.Answer:A. rhizome