Correct option is D
· Corms are used for propagation in crops like gladiolus, not chrysanthemum.
· Y2K is a variety of chrysanthemum, commonly cultivated for decorative and commercial purposes.
· De-suckering is a cultural practice in chrysanthemum to improve plant growth and flowering.
· Chrysanthemum is a short-day plant, meaning it requires long nights to initiate flowering.