Gladiolus is propagated by which method?

Answer: Option B

Gladiolus is propagated by bulbs.
Gladiolus is propagated by bulbs (the underground storage organs - which are sometimes wrongly called corms and cormels. The cormels of the first year would be normally of very small size and would not yield any flowers.
Dig up each corm and remove the small cormlets from the bottom. Store them over the winter and plant them in the spring.