Verification of truth — biological necessity: A tree always has which of the following?

Introduction / Context:
Trees vary widely in visible structures over seasons and lifecycles. We must choose the structure that is universally present in the organism’s biology.

Given Data / Assumptions:

• Leaves can be absent seasonally (deciduous dormancy) or reduced in certain taxa.
• Fruits/flowers are lifecycle stages and not present continuously; gymnosperms lack true flowers and fruits.
• Roots (of some form) are essential for water/nutrient uptake and anchorage throughout the tree’s life.

Concept / Approach:
Test universality across taxa and seasons. Roots are fundamental organs across trees, even if specialized (buttress, aerial roots) or submerged.

Step-by-Step Solution:
Eliminate non-universal (leaves, flowers, fruits).Select “Roots.”

Verification / Alternative check:
Seedlings rapidly form root systems; a “tree” without roots would be non-viable outside extremely artificial conditions.

Why Other Options Are Wrong:
They are conditional on season/species and not constant.

Common Pitfalls:
Generalizing from everyday leafy appearance to universality.

Final Answer:
Roots