The process by which water moves up the xylem against gravity is mainly due to: MCQ with Answer and Explanation

The process by which water moves up the xylem against gravity is mainly due to:
A. Capillarity
B. Active pumping
C. Root pressure
D. Transpiration-cohesion-tension
Answer: Option D
Solution (By JKSSB Mock Tests)
The cohesion-tension theory states that transpiration from leaves creates tension, pulling water up the xylem; water molecules cohere, forming a continuous column. Root pressure is minor.

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