The stem of Turmeric is

(a) Corm

(b) Bulb

(c) Rhizome

(d) Tuber

The turmeric stem is an example of a rhizome. Rhizomes often appear as a sympodial axis, meaning the lateral branches grow opposite to the leaves. They are also referred to as rootstocks. Other examples of edible rhizomes include canna, ginger, and water lily. Rhizomes can branch in two ways: monopodial or sympodial.

Additional Information:

• Corm: A corm is a short, thick, and unbranched underground stem with buds at its nodes. Examples include Alocasia, Gladiolus, Colocasia, Crocus, Colchicum, and Freesia. Corms are covered by thin sheathing leaves called scales.
• Bulb: A bulb is a short underground stem with a fleshy leaf base (scales). It contains a reduced, disc-like stem, and the shape of the bulb is typically convex or conical with highly compressed internodes.
• Tuber: A tuber forms when an underground stem enlarges at the tips due to stored food (usually starch). Potato is a classic example. Tubers have lenticels for gaseous exchange. Other examples include Cyperus, Helianthus, and Stachys. In tubers, eye buds develop into shoots, and adventitious roots grow from the base.

Conclusion: Based on the characteristics described, the correct answer is: “Rhizome.”