Branch : Stem : Leaf — From the options, pick the plant part that keeps the category consistency with the given trio of plant structures.

Introduction / Context:
The items 'Branch : Stem : Leaf' all belong to the class of plant parts (morphological structures). The task is to identify from the options another member of this same category and avoid items that are not plant parts.

Given Data / Assumptions:

• Branch, stem, and leaf are canonical plant organs/structures.
• Options mix living and non-living items and a plant part.
• We require a choice that is itself a plant part.

Concept / Approach:
'Root' is a fundamental plant organ like stem and leaf. 'Tree' denotes the whole organism, not a part; 'Chair' and 'Glass' are man-made objects. Therefore, the only option maintaining the plant-part category is 'Root'.

Step-by-Step Solution:
1) Determine the shared class: plant morphological parts.2) Evaluate options for membership in this class.3) 'Root' is a plant organ parallel to 'stem' and 'leaf'. Others are not plant parts.4) Choose 'Root'.

Verification / Alternative check:
Basic botany lists four primary organs: root, stem, leaf, and flower (with derivatives). Root therefore matches the category directly.

Why Other Options Are Wrong:

• Tree: Whole plant (organism level), not an organ.
• Chair/Glass: Inanimate artifacts; category mismatch.
• None of these: Incorrect since 'Root' is valid.

Common Pitfalls:
Choosing the whole (tree) when the set contains parts. Maintain the same granularity.

Final Answer:
Root