Step 1: Understanding the Question:
This question tests knowledge of eutrophication.
Step 2: Detailed Explanation:
Eutrophication is associated with water pollution.
It is the enrichment of water bodies with nutrients, leading to algal blooms.
Noise (A): Not related.
Radiation (B): Not related.
Air (C): Not related.
Thus, the correct answer is water.
Step 3: Final Answer:
Thus, eutrophication is associated with water pollution, which corresponds to option (D).
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