How can underground stem be differentiated from a root?

An underground stem can be differentiated from a root on the basis of following points:

(i) Absence of root cap.

(ii) Absence of root hair.

(iii) Presence of terminal bud.

(iv) Presence of nodes and internodes.

(v) Occurrence of foliage or scale leaves on the nodes.

(vi) Presence of axillary buds on the nodes.

(vii) Exogenous branching.

(viii) Stem-like internal structure.