Concept:Modified underground stems serve as food storage organs and differ in shape, structure, and growth direction.
Explanation:A corm is a short, vertical, swollen underground stem that stores food.
It is solid inside and covered by thin, dry scale leaves.
Examples of corm-producing plants include crocus and gladiolus.
A bulb, such as an onion, consists of fleshy scale leaves attached to a small stem disc, not a solid vertical stem.
A rhizome grows horizontally underground, as seen in ginger.
A tuber is a swollen stem tip or root, such as the Irish potato.
The description "short, vertical underground stem" matches a corm exactly.
Answer:B. Corm
