Official Answer Key & Detailed Solution
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Correct Answer: Option (C) — Phosphorus cycle
Concept & Option Breakdown
Standard Reference VerifiedThe phosphorus cycle is a sedimentary biogeochemical cycle that lacks a significant atmospheric component. The principal natural reservoir of phosphorus is rock minerals (such as apatite), from which phosphate ions (PO₄³⁻) are released into soils and water primarily via weathering of rocks.
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